WO2020059184A1 - Evaluation method, evaluation program, and production method for powder for metal additive manufacturing, information processing device, and metal additive manufacturing device - Google Patents

Evaluation method, evaluation program, and production method for powder for metal additive manufacturing, information processing device, and metal additive manufacturing device Download PDF

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WO2020059184A1
WO2020059184A1 PCT/JP2019/010680 JP2019010680W WO2020059184A1 WO 2020059184 A1 WO2020059184 A1 WO 2020059184A1 JP 2019010680 W JP2019010680 W JP 2019010680W WO 2020059184 A1 WO2020059184 A1 WO 2020059184A1
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powder
metal
metal powder
additive manufacturing
impedance
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PCT/JP2019/010680
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French (fr)
Japanese (ja)
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千葉　晶彦
貴浩 工藤
健大 青柳
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技術研究組合次世代３Ｄ積層造形技術総合開発機構
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Priority to JP2020547921A priority Critical patent/JP6980126B2/en
Publication of WO2020059184A1 publication Critical patent/WO2020059184A1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/16—Metallic particles coated with a non-metal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/10—Sintering only
    • B22F3/105—Sintering only by using electric current other than for infrared radiant energy, laser radiation or plasma ; by ultrasonic bonding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/12—Both compacting and sintering
    • B22F3/16—Both compacting and sintering in successive or repeated steps
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y30/00—Apparatus for additive manufacturing; Details thereof or accessories therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y40/00—Auxiliary operations or equipment, e.g. for material handling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y50/00—Data acquisition or data processing for additive manufacturing
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/25—Process efficiency

Definitions

  • the present invention relates to a material for metal additive manufacturing.
  • Patent Document 1 discloses a technique of three-dimensional additive manufacturing using metal powder.
  • preheating or presintering at a temperature of 50% to 80% of the melting point of the alloy is performed in advance.
  • preheating of the metal powder is performed as a measure against charge-up. It is desired that the preheating temperature at this time be as low as possible. The reason for this is that the higher the preheating temperature, the longer the preheating time and the cooling time after the completion of modeling. Further, the higher the preheating temperature, the stronger the bond between the metal powders, and the more difficult it becomes to remove unnecessary powder after the additive manufacturing. However, if the preheating temperature is too low, a smoke phenomenon occurs and the additive manufacturing itself fails.
  • the material used for additive metal manufacturing is a material that can lower the preheating temperature without causing a smoke phenomenon.
  • An object of the present invention is to provide a technique for solving the above-mentioned problem.
  • an impedance measuring step of measuring the impedance of the metal powder Capacitive component extraction step of extracting a capacitive component from the measured impedance, When the capacity component of the metal powder becomes zero, an evaluation step of evaluating a powder material for metal additive manufacturing that does not cause a smoke phenomenon upon irradiation with an electron beam, including.
  • the metal additive manufacturing powder evaluation program An impedance obtaining step of obtaining the impedance of the metal powder, A capacitance component extraction step of extracting a capacitance component from the obtained impedance, When it is determined that the capacitance component of the metal powder becomes zero, an evaluation step of evaluating a metal additive manufacturing powder material that does not cause a smoke phenomenon at the time of electron beam irradiation, On a computer.
  • an information processing device includes: Impedance obtaining means for obtaining the impedance of the metal powder, Capacitance component extraction means for extracting a capacitance component from the obtained impedance, When it is determined that the capacitance component of the metal powder becomes zero, an evaluation unit that evaluates to be a powder material for metal additive manufacturing that does not cause a smoke phenomenon upon irradiation with an electron beam, Is provided.
  • a method for producing a powder for metal additive manufacturing An impedance measuring step of measuring the impedance of the metal powder, Capacitive component extraction step of extracting a capacitive component from the measured impedance, When the capacity component of the metal powder becomes zero, an evaluation step of evaluating a powder material for metal additive manufacturing that does not cause a smoke phenomenon upon irradiation with an electron beam, In the evaluation step, when the metal powder is not evaluated as the metal additive manufacturing powder material, a surface treatment step of performing a mechanical treatment including collision of the metal powder on the metal powder or a metal coating treatment on the surface of the metal powder. When, including.
  • a metal additive manufacturing apparatus includes: A metal additive manufacturing apparatus for selectively dissolving and solidifying the spread metal powder by an electron beam to form a metal additive product, Impedance obtaining means for obtaining the measured impedance of the metal powder, Capacitance component extraction means for extracting a capacitance component from the obtained impedance, When it is determined that the capacitance component of the metal powder becomes zero, an evaluation unit that evaluates to be a powder material for metal additive manufacturing that does not cause a smoke phenomenon upon irradiation with an electron beam, When the evaluating means evaluates the metal additive manufacturing powder material, a laminate modeling means for modeling a metal additive model using the metal powder, Is provided.
  • a control program for an information metal additive manufacturing apparatus includes: A control program of a metal additive manufacturing apparatus for selectively melting and solidifying the spread metal powder with an electron beam to form a metal additive manufacturing object, Impedance acquisition step of acquiring the measured impedance of the metal powder, A capacitance component extraction step of extracting a capacitance component from the obtained impedance, When it is determined that the capacitance component of the metal powder becomes zero, an evaluation step of evaluating a metal additive manufacturing powder material that does not cause a smoke phenomenon at the time of electron beam irradiation, In the evaluation step, when it is evaluated that the metal additive manufacturing powder material, the additive manufacturing step of modeling the metal additive using the metal powder, On a computer.
  • the present invention can be evaluated as a powder for metal additive manufacturing that does not cause a smoke phenomenon even when the preheating temperature is lowered.
  • FIG. 4 is a view showing a metal powder after a mechanical pretreatment according to the first embodiment of the present invention.
  • FIG. 3 is a view showing a surface image (SEM) of the metal powder after the mechanical pretreatment according to the first example of the present invention.
  • FIG. 4 is a view showing a surface analysis result (XPS) of the metal powder after the mechanical pretreatment according to the first example of the present invention.
  • FIG. 2 is a view illustrating a powder electric resistance measuring device for measuring a resistance value of a metal powder according to a first embodiment of the present invention. It is a figure which shows the electric resistance measurement jig
  • FIG. 3 is a view for explaining the principle of measuring the electric resistance of a powder obtained by measuring the resistance of a metal powder according to the first embodiment of the present invention.
  • FIG. 4 is a diagram illustrating a measurement connection and a measurement circuit for measuring a resistance value of a metal powder according to the first example of the present invention.
  • FIG. 4 is a diagram illustrating a change in impedance of the metal powder after the mechanical pretreatment according to the first example of the present invention.
  • FIG. 4 is a diagram illustrating a change in a capacitance component obtained from the impedance of the metal powder after the mechanical pretreatment according to the first example of the present invention.
  • FIG. 3 is a view for explaining the principle of measuring the electrical resistance of the powder obtained by measuring the impedance of the metal powder according to the first embodiment of the present invention.
  • FIG. 4 is a diagram illustrating a measurement connection and a measurement circuit for measuring the impedance of the metal powder according to the first example of the present invention. It is a figure showing the result of the smoke test with the metal powder after the mechanical pretreatment concerning a 1st example of the present invention.
  • FIG. 1 It is a figure which shows the surface analysis result (XPS) of the metal powder after the surface coating process which concerns on the 3rd Example of this invention. It is a figure showing the temperature change of the resistance value of metal powder after surface coating processing concerning a 3rd example of the present invention. It is a figure showing change of impedance of metal powder after surface coating processing concerning a 3rd example of the present invention. It is a figure showing the result of the smoke test with the metal powder after surface coating processing concerning a 3rd example of the present invention. It is a figure showing an example of the alloy powder which can be used in an embodiment of the present invention. It is a block diagram showing composition of a metal additive manufacturing device concerning an embodiment of the present invention.
  • XPS surface analysis result
  • SEM surface image
  • FIG. 1A is a flowchart illustrating a manufacturing procedure of the metal additive manufacturing powder according to the present embodiment.
  • step S101 an evaluation process is performed on a metal powder to be evaluated.
  • step S103 it is determined from the evaluation result whether the evaluation is good. If the evaluation result of the metal powder is good (YES), the manufacturing processing procedure ends. On the other hand, when the evaluation result of the metal powder is not good (NO), the surface treatment of the metal powder, in particular, the treatment of the surface oxide is performed in step S105.
  • FIG. 1B is a flowchart showing the procedure of the metal powder evaluation process (S101) according to the present embodiment.
  • step S111 the impedance of the metal powder to be evaluated is measured.
  • the measurement is performed while changing the temperature of the metal powder.
  • the temperature change is gradually increased from normal temperature to 800 ° C.
  • step S113 a capacitance component is calculated by an equivalent circuit of the metal powder based on the measured impedance.
  • step S115 it is determined whether or not the temperature at which the calculated capacity component approaches zero is lower than a predetermined temperature ⁇ .
  • the predetermined temperature ⁇ is, for example, 200 ° C. or 400 ° C. as a standard.
  • step S115 If it is determined in step S115 that the temperature at which the capacitance component approaches zero is lower than the predetermined temperature ⁇ , in step S117, the metal powder to be evaluated is a good metal additive manufacturing powder that does not cause a smoke phenomenon even with relatively low preliminary heating. judge.
  • step S119 when the temperature at which the capacitance component approaches zero is higher than the predetermined temperature ⁇ , in step S119, the poor metal additive manufacturing powder that requires relatively high preheating to prevent the metal powder to be evaluated from generating a smoke phenomenon. Is determined.
  • FIG. 2 is a diagram illustrating evaluation criteria for the metal powder according to the present embodiment. Hereinafter, the evaluation criteria for the metal powder will be described in detail.
  • Metal additive manufacturing processes are broadly classified into the following powder bed forming processes, preheating and selective melting processes, and unmelted powder recovery processes.
  • ⁇ Powder bed formation process> This is the most basic process for performing modeling without creating unmelted defects. For that purpose, it is required that the shape of the metal powder used is close to a true sphere and that the powder surface has no satellite.
  • the irregular shape powder having satellites has poor fluidity, so that the thickness of the powder bed (powder bed) becomes uneven, and the molten pool (melt pool) becomes unstable, which causes formation of solidification defects.
  • powder with a particle size distribution of about 40 to 100 ⁇ m is used, but powder with a finer particle size distribution of about 10 to 50 ⁇ m is expected in order to improve the surface roughness of the molded article. The use of is also being considered.
  • Electron beam additive manufacturing is based on a hot process in which the powder bed is preheated before the powder bed melting process. This is because when an electron beam is applied to an unheated powder bed, the powder scatters and soars into smoke (called “smoke"), and the powder bed disappears and is lost, preventing normal modeling. It is.
  • An oxide film is formed on the surface of the metal powder, and functions as a capacitor (capacitor) that can store negative charges of the electron beam.
  • the electrical resistance of the oxide film is high at room temperature, but it is considered that the oxide film exhibits semiconductor properties that decrease with increasing temperature.
  • the preheating temperature is too high, the contact portions of the individual powders are partially melted during molding to form a strong bonding portion, and it becomes difficult to pulverize the powder bed by the above-mentioned blast treatment, and the state of the raw material powder Can not be returned to. In such a case, not only the powder cannot be reused, but also it becomes impossible to separate the molded object and the unmelted powder, so that the part production ends in failure.
  • the preheating is effective as an advantage in controlling the material and shape of the formed object, and the electron beam additive manufacturing employing the hot process is advantageous in forming the material having poor ductility such as an intermetallic compound. Become.
  • Metals are electrically good conductors, and if they are grounded when irradiated with an electron beam, they will not be charged (negatively), so the metal bulk can be continuously irradiated with the electron beam and melted be able to.
  • the melting process is not simple because an electron beam is applied to a powder bed having a particle size distribution of about 40 to 150 ⁇ m. As will be described later, when the electrical resistivity of the metal powder bed is measured at room temperature, the value is on the order of 107 ⁇ m or more.
  • the oxide film is formed on the surface of the metal powder as described above, and most of them behave electrically as a semiconductor, so that the contact resistance between the powders at room temperature is high. It is considered that the electric resistance of the powder bed, which is the deposit, behaves more like a semiconductor than a metallic one.
  • the oxide film on the surface of the metal powder behaves like a semiconductor, and the electrical resistance decreases as the temperature rises. It is thought to be to get up. Furthermore, if the preheating temperature for avoiding the smoke phenomenon is too high, the partial melting at the contact portions of the individual powders proceeds during molding, the solidification of the powder bed progresses, and the separation of the molten and unmelted portions occurs. Care must be taken because it becomes difficult and hinders the modeling.
  • Temperature dependence of DC electrical resistivity of alloy powder The change in electrical resistivity between the temperature rise process from room temperature to 800 ° C and the temperature drop process measured by the DC four-terminal method was measured. Although the value of resistivity near room temperature changes, the value of electrical resistivity decreases rapidly with increasing temperature, showing the temperature dependence of electrical resistance like an oxide (semiconductor). The resistivity is on the order of 10-4 ⁇ m. At higher temperatures, the temperature dependence almost disappears up to 800 ° C. This suggests that the electrical properties of the surface oxide film of the alloy powder change from oxide to metallic electrical conductivity at a high temperature of 600 ° C or higher.
  • the value of the electrical resistivity does not return to the original value, and the value of the resistivity hardly changes to room temperature, showing a large hysteresis.
  • smoke is eliminated by heating the alloy powder at about 650 ° C, and electron beam additive manufacturing becomes possible as described above. To be understood.
  • Equation 2 shows, as an example, a result 203 obtained by fitting the equation 202 to a Cole-Cole plot from room temperature to 200 ° C. From this figure, it can be seen that the measured Cole-Cole plot fits well to Equation 202, and as an equivalent circuit 201, as shown in FIG. 2, the resistance (R oxide ) of the surface oxide of the alloy powder and the capacitor (C An electrical circuit is obtained in which a parallel circuit of oxide ) is coupled in series with the bulk electrical resistance ( Rmetal ) of the alloy powder.
  • Table 204 collectively shows the resistance values and the capacitance values obtained by the fitting.
  • the Cole-Cole plot at a temperature of 300 ° C. or more converges near the origin, suggesting that the resistance component of R oxide is dominant as the impedance component of the surface oxide film.
  • the equivalent circuit in this case can be expressed as a circuit in which the bulk electrical resistance (R metal ) and the resistance (R oxide ) of the surface oxide of the alloy powder are connected in series. This means that the powder bed is preheated, so that the capacitor component C oxide disappears, suggesting that the powder bed changes to an electrical structure in which charge accumulation does not occur. It is considered that smoke is not generated even by beam irradiation. In the actual electron beam additive manufacturing, for example, in the case of titanium alloy powder, the generation of smoke is eliminated by preheating at about 650 ° C.
  • the oxide film on the powder surface has low thermal stability, which is considered to be a cause of the disappearance of the capacitor component C oxide by preheating.
  • the powder bed is charged to a negative charge by electron beam irradiation, and smoke is generated due to the capacitor component caused by the oxide film on the surface of the alloy powder. This is due to C oxide, and by eliminating this, the generation of smoke can be suppressed.
  • the powder bed is pre-heated.
  • the technology can avoid smoke other than pre-heat. Be the law.
  • the purpose is to remove the residual stress of the modeled object generated during the modeling process
  • the preheating temperature is set at 500 to 600 ° C. Therefore, the technology for dissipating the capacitor C oxide other than the preheating can significantly lower the conventional preheating temperature, and does not cause the problem of solidification due to the partial fusion bonding of the powder of the powder bed in the preheating process.
  • the scope of application of electron beam additive manufacturing technology will be dramatically expanded.
  • the pre-sintering temperature can be lowered.
  • the normal preheating temperature from 1150 ° C. to 600 to 500 ° C. without generating a smoke phenomenon.
  • Example 1 is a case where a mechanical pretreatment is performed by a jet mill.
  • Example 2 is a case where mechanical pretreatment was performed by a ball mill.
  • Example 3 is a case where a metal plating process is performed.
  • the comparative example is a case where the preliminary treatment is not performed.
  • Example 1 ⁇ Used metal powder ⁇
  • a nickel-based alloy powder of Inconel 718 (registered trademark) produced by a gas atomizing method was used.
  • FIG. 3A shows an SEM (Scanning Electron Microscope) image and a particle size distribution 120.
  • FIG. 7 shows a principle diagram of the jet mill.
  • the input non-mechanical treated metal powder is stirred by the injected high-pressure gas (N 2 gas in FIG. 7) and repeats collision. Then, the metal powder after the mechanical treatment is discharged. It is desirable that the metal powder be heated to 100 ° C. to 300 ° C. during the mechanical treatment in order to reduce the capacity component.
  • FIG. 3A shows an SEM image and a particle size distribution.
  • FIG. 3A shows a SEM image and a particle size distribution 110 of Inconel 718 obtained by a commercially available plasma atomizing method, a SEM image and a particle size distribution 120 of Inconel 718 obtained by the gas atomizing method, and after performing a mechanical pretreatment.
  • the SEM image and the particle size distribution 130 of Inconel 718 by the above-mentioned gas atomization method are shown in comparison.
  • the particle diameter is averaged by the mechanical pretreatment, but there is no difference in the overall SEM image and the particle size distribution that is considered to lead to a reduction in preheating. That is, it was observed that fine powder had been removed by mechanical pretreatment (stirring with a high-speed, high-pressure gas stream). Further, as compared with the plasma atomized powder, the shape of the powder was not spherical but slightly deformed and an end face was observed. However, there is no large difference in the particle size distribution, and they are almost equal.
  • FIG. 3B shows an enlarged SEM image 230 of the surface of the powder particle after the mechanical pretreatment and enlarged SEM images 210 and 220 of the surface of the powder particle without the mechanical pretreatment.
  • the solidified structure including the dendrite structure (dendrites) seen in the enlarged SEM images 210 and 220 is flattened in the enlarged SEM image 230 by the collision of the powder particles in the mechanical pretreatment.
  • the flattening (reducing) of the solidified structure including the dendland structure may lead to a reduction in preheating. That is, the powder before the mechanical pretreatment had a dendritic structure, but after the mechanical pretreatment, no dendrites were observed and the surface was flat. Therefore, the presence of dendrites may have an effect.
  • FIG. 3C shows an XSP (X-ray photoelectron spectroscopy) analysis result 330 of the surface of the powder particles after the mechanical pretreatment and an XSP analysis result 310 of the surface of the powder particles without the mechanical pretreatment. And are shown in contrast.
  • XSP X-ray photoelectron spectroscopy
  • FIG. 4B is a diagram showing a powder electric resistance measuring device 420.
  • a metal powder to be measured is set in a high-temperature powder resistance measuring vacuum furnace 430, and electric resistance is measured.
  • FIG. 4C is a diagram showing a powder electric resistance measuring jig 440 and a temperature pattern 450.
  • the measurement conditions are, for example, an atmosphere pressure: less than 0.01 Pa, an inner diameter of the powder-filled cylinder: ⁇ 10 mm, and a powder height: 10 mm.
  • the powder electric resistance measuring device 420 gradually increases the metal powder from room temperature (RT) to 800 ° C., holds the metal powder for a predetermined time, and measures the electric resistance while gradually lowering the metal powder. Specifically, (1) start from room temperature, (2) heat to 800 ° C (heating rate 5 ° C / min), (3) hold at 800 ° C for 1 hour, (4) cool to room temperature (cooling rate 5 °C / min).
  • FIG. 4D is a diagram showing a measurement outline 460 in the powder electric resistance measuring device 420 and a structure 470 in the vacuum furnace 430 for measuring a high-temperature powder resistance. Powder electrical resistance is measured by a DC resistance meter.
  • FIG. 4E shows a DC electrical resistance measurement connection 480 and a DC electrical resistance measurement circuit diagram 490.
  • FIG. 4A is a diagram showing a change in electric resistance measured according to FIGS. 4B to 4E.
  • the metal powder 130 after the mechanical pretreatment has a lower electric resistance than the metal powders 110 and 120 without the mechanical pretreatment consistently at the room temperature (RT) before heating. Since the sintering property is low (high conductivity), the sinterability by the electron beam is improved, and the sintering is easily performed in a short time, so that the preheating temperature can be lowered.
  • FIG. 5D shows an AC impedance measurement connection 580 and an AC impedance measurement circuit diagram 590.
  • FIG. 5A is a diagram showing a change in impedance measured according to FIGS. 5B and 5C.
  • FIG. 5A is a so-called Cole-Cole plot.
  • the Cole-Cole plot 510 of the metal powder of the plasma atomization method without mechanical pretreatment shows that the impedance is in the order of 5 digits (X0000 ⁇ ) at 200 ° C. Further, according to the enlarged plot 520, the value is in the order of three digits (X00 ⁇ ) at 300 ° C., and becomes a small value exceeding 400 ° C.
  • the metal powder of the gas atomization method after the mechanical pretreatment of this embodiment cuts three digits (100 ⁇ ) at 100 ° C., and becomes one digit (X ⁇ ) or less when the temperature exceeds 200 ° C.
  • FIG. 5B is a calculation result of the capacitance component calculated by the equivalent circuit model 540 from the impedance measurement result of FIG. 5A.
  • FIG. 5B shows a capacity component 550 of the metal powder of the plasma atomization method without the mechanical pretreatment and a capacity component 560 of the metal powder of the gas atomization method after the mechanical pretreatment of the present embodiment.
  • the capacitance component of the equivalent circuit model 540 is reduced by the mechanical pretreatment of the present embodiment, and further closes to zero at a low temperature (about 200 ° C.). It is expected that the smoke phenomenon due to the irradiation will not occur (is suppressed).
  • FIG. 6B is a diagram illustrating a smoke test method using metal powder.
  • the procedure 640 was performed under the conditions 650.
  • an element technology research machine (electron beam processing machine) (Tada Electric Co., Ltd.) was used.
  • FIG. 6A is a diagram showing a result 610 of the smoke test using the metal powder.
  • the result 610 of FIG. 6A shows the smoke test result of the metal powder of the plasma atomization method without the mechanical pretreatment and the smoke test result of the metal powder of the gas atomization method after the mechanical pretreatment of the present example. .
  • the smoke phenomenon occurs even by the preheating at 950 ° C.
  • the smoke phenomenon occurs until the preheating reaches 450 ° C., but the smoke phenomenon does not occur when the temperature reaches 650 ° C.
  • FIG. 6A there is a possibility that the smoke phenomenon does not occur even in preheating at 500 ° C. to 600 ° C.
  • FIG. 8C shows a planetary ball mill 840 and the principle 850 of the ball mill.
  • the planetary ball mill Classic Line P-7 (Fritsch, Germany) was used as the ball mill.
  • the disk rotation speed (revolution) is 800 RPM
  • the pot rotation speed (rotation) is 1600 RPM
  • the ball diameter is ⁇ 5 mm.
  • the processing time was 15 minutes for the counterclockwise revolution and 15 minutes for the clockwise revolution. It is desirable that the metal powder be heated to 100 ° C. to 300 ° C. during the mechanical treatment in order to reduce the capacity component.
  • the ball mill treatment was not particularly heated, and the temperature of the container immediately after the treatment was 100 ° C. or higher due to the frictional heat of the balls. Therefore, it is considered that the mechanical treatment while heating at 100 ° C. to 200 ° C. can more effectively reduce the electric resistance and the capacitance component.
  • FIG. 8A is a diagram showing a surface image (SEM) 810 and an enlarged SEM image 820 of the metal powder after the mechanical pretreatment of the present example.
  • FIG. 8B is a diagram illustrating a change in impedance of the metal powder after the mechanical pretreatment according to the present example. It can be seen that the impedance value is extremely small compared to the impedance of the metal powder without mechanical pretreatment (see 510 in FIG. 5A). From this, it can be predicted that the capacity component is small and approaches zero with low preheating.
  • FIG. 13 shows a planetary ball mill 840 and processing conditions 1310 by the ball mill.
  • a ball mill a planetary ball mill Classic Line P-7 (Fritsch, Germany) was used.
  • the disk rotation speed (revolution) is 800 RPM
  • the pot rotation speed (rotation) is 1600 RPM
  • the ball diameter is ⁇ 5 mm.
  • the processing time was a total of 30 minutes, that is, 15 minutes for the counterclockwise revolution and 15 minutes for the clockwise revolution.
  • the temperature of the metal powder was 100 ° C. to 300 ° C.
  • FIG. 14A is a diagram showing a surface image (SEM) of a metal powder (Inconel 718 / IN718) before and after mechanical pretreatment according to the present example.
  • the upper left diagram is an SEM image 1410 before ball milling
  • the upper right diagram is an SEM image 1420 after ball milling
  • the lower left diagram is an enlarged SEM image 1411 before ball milling
  • the lower right diagram is an enlarged SEM image 1421 after ball milling.
  • FIG. 14B is a diagram illustrating a temperature change of the resistance value and a temperature change of the impedance of the metal powder (Inconel 718 / IN718) after the mechanical pretreatment according to the present example.
  • the measurement of the electrical characteristics of the surface of the metal powder was performed using the same apparatus as in Example 1.
  • a graph 1430 in FIG. 14B is a diagram illustrating a change in electric resistance measured according to FIGS. 4B to 4E.
  • the resistivity of the metal powder after ball milling (Inconel 718 / IN718) is consistent with the resistivity of metal powder without ball milling from room temperature (RT) before heating. (High conductivity), the chargeability of the metal powder by electron beam irradiation is weakened even in a low temperature region, and the preheating temperature can be lowered.
  • a graph group 1440 in FIG. 14B is a diagram illustrating a change in impedance of the metal powder (Inconel 718 / IN718) before and after the ball mill processing according to the present example.
  • the upper right graph 1441 of the graph group 1440 is the impedance of the metal powder without ball milling
  • the left graph 1442 of the graph group 1440 is the impedance of the metal powder after the ball milling
  • the lower right graph 1443 of the graph group 1440 is the left graph 1442. It is an enlarged graph near an origin.
  • the impedance of the metal powder after ball milling is extremely smaller than the impedance of the metal powder without ball milling. From this, it can be predicted that the capacity component is small and approaches zero with low preheating.
  • FIG. 14C is a diagram illustrating a capacitance component obtained based on an equivalent circuit model from the measurement result of the impedance after the ball mill processing according to the present embodiment.
  • an equivalent circuit simulation result 1451 is a simulation result from the impedance measurement result of the graph 1444
  • an equivalent circuit model 1452 is based on the equivalent circuit simulation result 1451.
  • 5 is an equivalent circuit model of a metal powder (Inconel 718 / IN718) after ball milling. From the equivalent circuit model 1452 in FIG. 14C, it can be seen that no capacitance component is seen in the impedance measurement result.
  • the results of the measurement of the impedance can provide a powder for metal additive manufacturing that does not cause a smoke phenomenon even when the preheating temperature is lowered, similarly to the mechanical pretreatment using a jet mill, by ball milling.
  • FIG. 14D is a diagram showing an XPS analysis result of the metal powder (Inconel 718 / IN718) after the mechanical pretreatment according to the present example.
  • Such XPS analysis results are for verifying the change in the material of the metal powder (Inconel 718 / IN718) due to the ball mill treatment.
  • Ti64 The product of Daido Steel Co., Ltd. was used as titanium 64.
  • Table 2 shows the properties of the titanium 64 used.
  • FIG. 15A is a diagram showing a surface image (SEM) of the metal powder (titanium 64 / Ti64) before and after the mechanical pretreatment according to the present example.
  • the upper left figure is the SEM image 1510 before the ball mill processing
  • the upper right figure is the SEM image 1520 after the ball mill processing
  • the lower left diagram is an enlarged SEM image 1511 before ball milling
  • the lower right diagram is an enlarged SEM image 1521 after ball milling.
  • FIG. 15B is a diagram showing a temperature change of the resistance value and a temperature change of the impedance of the metal powder (titanium 64 / Ti64) after the mechanical pretreatment according to the present example.
  • the measurement of the electrical characteristics of the surface of the metal powder was performed using the same apparatus as in Example 1.
  • a graph 1530 in FIG. 15B is a diagram illustrating a change in the electric resistance measured according to FIGS. 4B to 4E.
  • the resistivity of the metal powder (titanium 64 / Ti64) after ball milling is consistent with the resistivity of metal powder without ball milling from room temperature (RT) before heating. Since it is the same or lower (higher conductivity), the chargeability of the metal powder by electron beam irradiation is weakened even in a low temperature range, and the preheating temperature can be lowered.
  • a graph group 1540 in FIG. 15B is a diagram illustrating a change in impedance of the metal powder (titanium 64 / Ti64) before and after the ball mill treatment according to the present embodiment.
  • the upper right graph 1541 of the graph group 1540 is the impedance of the metal powder without ball milling
  • the left graph 1542 of the graph group 1540 is the impedance of the metal powder after ball milling
  • the lower right graph 1543 of the graph group 1540 is the left graph 1542 of the left graph 1542. It is an enlarged graph near an origin.
  • the impedance of the metal powder after ball milling is extremely smaller than the impedance of the metal powder without ball milling. From this, it can be predicted that the capacity component is small and approaches zero with low preheating.
  • FIG. 15C is a diagram showing an XPS analysis result of the metal powder (titanium 64 / Ti64) after the mechanical pretreatment according to the present example.
  • the result of the XPS analysis is to verify a change in the material of the metal powder (titanium 64 / Ti64) due to the ball mill treatment.
  • TiAl The product of Daido Steel Co., Ltd. was used as TiAl. Table 3 shows the characteristics of the TiAl used.
  • FIG. 16A is a diagram showing a surface image (SEM) of a metal powder (titanium aluminum alloy / TiAl) before and after mechanical pretreatment according to the present example.
  • the upper left diagram is an SEM image 1610 before ball milling
  • the upper right diagram is an SEM image 1620 after ball milling
  • the lower left diagram is an enlarged SEM image 1611 before ball milling
  • the lower right diagram is an enlarged SEM image 1621 after ball milling.
  • FIG. 16B is a diagram showing a temperature change of the resistance value and a temperature change of the impedance of the metal powder (titanium aluminum alloy / TiAl) after the mechanical pretreatment according to the present example.
  • the measurement of the electrical characteristics of the surface of the metal powder was performed using the same apparatus as in Example 1.
  • a graph 1630 in FIG. 16B is a diagram illustrating a change in the electric resistance measured according to FIGS. 4B to 4E.
  • the resistivity of the metal powder (titanium aluminum alloy / TiAl) after ball milling is consistent with the resistivity of metal powder without ball milling from room temperature (RT) before heating. (Higher conductivity), the chargeability of the metal powder by electron beam irradiation is weakened even in a low temperature range, and the preheating temperature can be lowered.
  • a graph group 1640 in FIG. 16B is a diagram illustrating a change in impedance of the metal powder (titanium aluminum alloy / TiAl) before and after the ball mill treatment according to the present embodiment.
  • the upper right graph 1641 of the graph group 1640 is the impedance of the metal powder without ball milling
  • the left graph 1642 of the graph group 1640 is the impedance of the metal powder after ball milling
  • the lower right graph 1643 of the graph group 1640 is the left graph 1642 It is an enlarged graph near an origin.
  • the impedance of the metal powder after ball milling is extremely smaller than the impedance of the metal powder without ball milling. From this, it can be predicted that the capacity component is small and approaches zero with low preheating.
  • FIG. 16C is a diagram showing an XPS analysis result of the metal powder (titanium aluminum alloy / TiAl) after the mechanical pretreatment according to the present example.
  • FIG. 17A is a diagram showing a surface image (SEM) of a metal powder (copper powder / Cu) before and after mechanical pretreatment according to the present example.
  • the left figure is the SEM image 1710 before the ball mill processing
  • the right figure is the SEM image 1720 after the ball mill processing.
  • the solidified structure including the dendland structure dendritic crystal
  • FIG. 17B is a diagram illustrating a temperature change in the resistance value and a temperature change in the impedance of the metal powder (titanium aluminum alloy / TiAl) after the mechanical pretreatment according to the present example.
  • the measurement of the electrical characteristics of the surface of the metal powder was performed using the same apparatus as in Example 1.
  • a graph 1730 in FIG. 17B is a diagram illustrating a change in electric resistance measured according to FIGS. 4B to 4E.
  • the resistivity of the metal powder after the ball milling (copper powder / Cu) is consistent with the resistivity of the metal powder without the ball milling from room temperature (RT) before heating. Since it is the same or lower (higher conductivity), the chargeability of the metal powder by electron beam irradiation is weakened even in a low temperature range, and the preheating temperature can be lowered.
  • a graph group 1740 in FIG. 17B is a diagram illustrating a change in impedance of the metal powder (copper powder / Cu) before and after the ball mill processing according to the present example.
  • the upper right graph 1741 of the graph group 1740 is the impedance of the metal powder without ball milling
  • the left graph 1742 of the graph group 1740 is the impedance of the metal powder after ball milling
  • the lower right graph 1743 of the graph group 1740 is the left graph 1742 of the left graph 1742. It is an enlarged graph near an origin.
  • the impedance of the metal powder after ball milling is extremely small compared to the impedance of the metal powder without ball milling. From this, it can be predicted that the capacity component is small and approaches zero with low preheating.
  • FIG. 18 is a diagram illustrating a ball mill 840 that has undergone mechanical pretreatment according to the present embodiment and operating conditions 1810 at different times.
  • the conditions other than the processing time are the same as in the third embodiment.
  • FIG. 19 is a diagram showing a surface image (SEM) of the metal powder (Inconel 718 / IN718) after the mechanical pretreatment at different times according to the present example.
  • SEM surface image
  • FIG. 19 shows an SEM image 1910 after the processing for 10 minutes, an SEM image 1920 after the processing for 30 minutes, and an SEM image 1930 after the processing for 60 minutes.
  • FIG. 20 is a diagram showing a state 2010 of the metal powder (Inconel 718 / IN718) after the mechanical pre-treatment exceeding the appropriate time according to the present embodiment. That is, it is a diagram showing a state 2010 of the metal powder (Inconel 718 / IN718) after a 60-minute treatment by a ball mill 840. If the ball mill treatment is performed at 800 rpm for a long treatment time up to 60 minutes, the pulverized ball and the mill container and powder Was seen to be alloyed. Therefore, it is preferable that the ball mill treatment under these conditions does not exceed 60 minutes, and it is more preferable that the ball mill treatment is performed per 30 minutes.
  • FIG. 21 is a diagram illustrating a temperature change of the resistance value of the metal powder (Inconel 718 / IN718) after the mechanical pretreatment for different times according to the present example.
  • FIG. 21 shows the change in electrical resistance measured according to FIGS. 4B to 4E after mechanical pretreatment at different times.
  • the resistivity of the metal powder (Inconel 718 / IN718) after the ball mill treatment was consistent from room temperature (RT) before heating even after the ball mill treatment for 10 minutes and 30 minutes. Since the resistivity of the metal powder without ball milling is about the same as or lower than that of the metal powder (high conductivity), it is considered that the chargeability of the metal powder by electron beam irradiation is weakened even in a low temperature region and the preheating temperature can be lowered. . However, after the treatment for 60 minutes, the effect of lowering the resistivity by the preheating is small.
  • FIG. 22 is a diagram illustrating a temperature change of the impedance of the metal powder (Inconel 718 / IN718) after the mechanical pretreatment for different times according to the present example.
  • FIG. 22 shows an impedance measurement result 2210 after the 10-minute processing, an impedance measurement result 2220 after the 30-minute processing, and an impedance measurement result 2230 after the 60-minute processing.
  • the upper right graph 2211 of the impedance measurement result 2210 is the impedance of the metal powder without ball milling
  • the left graph 2212 is the impedance of the metal powder after ball milling
  • the lower right graph 2213 is an enlarged graph near the origin of the left graph 2212.
  • the upper right graph 2221 of the impedance measurement result 2220 is the impedance of the metal powder without ball milling
  • the left graph 2222 is the impedance of the metal powder after ball milling
  • the lower right graph 2223 is an enlarged graph near the origin of the left graph 2222.
  • the upper right graph 2231 of the impedance measurement result 2230 is the impedance of the metal powder without ball milling
  • the left graph 2232 is the impedance of the metal powder after ball milling
  • the lower right graph 2233 is an enlarged graph near the origin of the left graph 2232.
  • the impedance of the metal powder after ball milling is extremely smaller than the impedance of metal powder without ball milling. From this, it can be predicted that the capacity component is small and approaches zero with low preheating.
  • the ball mill treatment under this condition takes 60 minutes in 10 minutes or more. It is preferred not to exceed, and more preferably around 30 minutes. It is considered that the preferable time zone changes depending on operating conditions such as the ball size, the number of rotations, and the temperature.
  • FIG. 23 is a diagram illustrating a result 2310 of the smoke test using the metal powder after the mechanical pretreatment according to the present embodiment.
  • the smoke phenomenon could not be suppressed without the preheating at 700 ° C. or higher.
  • the mechanical pretreatment no smoke phenomenon occurred even at room temperature (RT). Therefore, depending on the conditions of the molten beam, the result was obtained that no smoke was generated even at room temperature without preheating.
  • RT room temperature
  • the smoke test that has obtained this result will be described.
  • FIG. 24 is a diagram illustrating a smoke test method using metal powder after mechanical pretreatment according to the present embodiment.
  • the smoke test system 2410 in FIG. 24 includes a beam irradiation control unit that controls the beam irradiation on the additive manufacturing metal powder to be subjected to the smoke test, and a metal powder observation unit that observes the state of the beam-irradiated additive manufacturing metal powder.
  • the beam irradiation control unit includes a modeling device (PC) that generates modeling data, a beam output control board that controls a beam output in response to a beam-on command from the modeling device, and a beam output signal from the beam output control board.
  • a beam output unit that outputs a beam.
  • the metal powder observation unit includes a high-speed camera for imaging the metal powder for additive manufacturing during the smoke test, an oscilloscope for controlling the imaging timing of the high-speed camera in synchronization with a control signal from the beam output control board, and a high-speed camera.
  • a camera control and storage device (PC) for controlling the speed camera to acquire and store the captured image.
  • FIG. 25 is a diagram showing smoke test conditions using metal powder after mechanical pretreatment according to the present example. That is, the smoke test condition includes the operation condition in the smoke test system 2410 of FIG.
  • FIG. 25 shows a camera condition 2510 of the high-speed camera, a structure 2520 of an arrangement portion for arranging the metal powder for additive manufacturing to be subjected to the smoke test, and a beam-on signal 2530 from the beam output control board.
  • Example 3 ⁇ Surface coating treatment ⁇ Next, a process of metal-coating the surface of the metal powder by plating will be described.
  • a plating apparatus “Flow Slooplator RP-1” manufactured by Uemura Kogyo Co., Ltd. was used. It should be noted that the same effect as the plating treatment was obtained by coating using a film forming method using "Hybridization System NHS-O” manufactured by Nara Machinery Co., Ltd.
  • FIG. 9A is a diagram showing a surface image (SEM) and a coating film thickness of 910 to 930 of the metal powder after the surface coating treatment according to the present example.
  • FIG. 9B is a diagram showing a surface analysis result (XPS) 940 of the metal powder after the surface coating treatment according to this example. According to FIG. 9B, the surface was not an oxide film but a hydroxyl group, and no oxide layer was observed.
  • XPS surface analysis result
  • FIG. 9C is a diagram illustrating a temperature change 950 of the resistance value of the metal powder after the surface coating treatment according to the present embodiment.
  • the metal powder after the metal coating treatment has lower electric resistance (higher conductivity) than the metal powder without the metal coating treatment from room temperature (RT) before heating.
  • RT room temperature
  • the chargeability of the metal powder by electron beam irradiation is weakened, and the preheating temperature can be further reduced.
  • FIG. 9D is a diagram illustrating a change 970 of the impedance of the metal powder after the surface coating treatment according to the present embodiment.
  • the metal powder after the metal coating treatment of the present example is lower than one digit (X ⁇ ) at all temperatures from room temperature (RT).
  • FIG. 9E is a diagram showing a result 980 of the smoke test using the metal powder after the metal coating treatment.
  • the result 980 in FIG. 9E shows the smoke test result of the metal atomized by the plasma atomizing method after the metal coating treatment of the present example and the smoke test result of the gas atomized by the gas atomizing method after the metal coating treatment.
  • the smoke phenomenon occurred up to 350 ° C., but did not occur from 450 ° C. Further, in the metal powder of the gas atomization method after the metal coating treatment of the present example, no smoke phenomenon occurred from room temperature (RT) (see 981 in FIG. 9E).
  • the electrical resistance and impedance are reduced, and by lowering the temperature at which the capacitance component approaches zero, the metal additive manufacturing that does not cause a smoke phenomenon even when the preheating temperature is reduced.
  • the electrical resistance and impedance are reduced, and the temperature at which the capacitance component approaches zero is reduced, so that the smoke phenomenon does not occur even if the preheating temperature is reduced.
  • the mechanical pretreatment by the jet mill and the ball mill is described. The same effect can be obtained without being limited to the ball mill.
  • the electrical resistance and impedance are reduced, and the temperature at which the capacitance component approaches zero is reduced, so that the metal additive manufacturing that does not cause a smoke phenomenon even if the preheating temperature is reduced.
  • surface coating treatment such as metal plating
  • alloy powder nickel-based alloy Inconel 718 (registered trademark: Inconel 718 / UNS Number N07718), titanium-based alloy such as titanium 64 or TiAl was used, but the alloy powder is not limited to this. .
  • FIG. 10 shows an example 1000 of another alloy powder to which the present invention can be applied.
  • These other alloy powders include other nickel-based alloys and other metal-based alloys containing a predetermined ratio of nickel, such as cobalt-based alloys, iron-based alloys, copper alloys, and tungsten alloys.
  • the metal additive manufacturing apparatus according to the embodiment of the present invention will be described.
  • the metal additive manufacturing apparatus according to the present embodiment has a function of performing the mechanical pretreatment of the present embodiment.
  • FIG. 11 is a block diagram illustrating a configuration of the metal additive manufacturing apparatus 1100 according to the present embodiment.
  • the metal additive manufacturing apparatus 1100 includes an information processing apparatus 1110 and an additive manufacturing apparatus 1120.
  • the information processing apparatus 1110 includes a communication control unit 1111, an input / output interface 1112, a display unit 1113, an operation unit 1114, and a storage medium as an option. Further, the information processing device 1110 includes a database 1115, an impedance acquisition unit 1116, a capacitance component calculation unit 1117, a metal powder evaluation unit 1118, and a preheating setting unit 1119.
  • the communication control unit 1111 controls communication with the modeling control unit 1121 of the additive manufacturing device 1120 and the external impedance measuring device 1130.
  • the input / output interface 1112 interfaces input and output with the display unit 1113, the operation unit 1114, and the storage medium. Note that the display unit 1113 and the operation unit 1114 may be combined as a touch panel.
  • the database 1115 holds data for the information processing device 1111 to perform the processing of the present embodiment. For example, an algorithm for calculating the capacitance component from the impedance and an algorithm for evaluating the metal powder from the capacitance component are stored. Also, a table for calculating a capacitance component from the impedance and a table for evaluating metal powder from the capacitance component are stored.
  • the impedance acquiring unit 1116 acquires the impedance information of the metal powder to be evaluated from the impedance measuring device 1130.
  • the impedance information of the metal powder to be evaluated may be obtained from a storage medium.
  • the capacitance component calculation unit 1117 calculates a capacitance component from the impedance information according to an algorithm stored in the database 1115.
  • the metal powder evaluation unit 1118 evaluates the metal powder to be evaluated according to the algorithm stored in the database 1115 based on the calculated capacity component.
  • the preheating setting unit 1119 sets a preheating temperature in the additive manufacturing apparatus 1120 based on a result of the metal powder evaluation unit 1118, an operation of an operator, and the like.
  • FIG. 12A is a diagram illustrating a display example of the information processing apparatus 1110 of the metal additive manufacturing apparatus 1100 according to the present embodiment.
  • the display example in FIG. 12A is realized by the display unit 1113 and the operation unit 1114 in FIG.
  • the display screen 1210 outputs a metal powder manufacturing company, a product name, and the like. Then, the evaluation result 1211 is output to the display screen 1210.
  • the characteristic that is the evaluation result 1211 is output, for example, a temperature 1212 at which the capacitance component becomes zero is output. Further, the necessity 1213 of the mechanical pretreatment or the surface coating treatment is output. Note that the output information is not limited to FIG.
  • FIG. 12B is a flowchart illustrating a processing procedure of the information processing apparatus 1110 of the metal additive manufacturing apparatus 1100 according to the present embodiment. This flowchart is executed by the CPU that controls the information processing device 1110 using the RAM, and implements the functional components of the information processing device 1110 in FIG.
  • step S1211 the information processing apparatus 1110 acquires impedance information of the metal powder to be evaluated.
  • step S1213 the information processing device 1110 calculates a capacitance component of the metal powder to be evaluated from the impedance.
  • step S1215 the information processing device 1110 determines whether or not the temperature at which the calculated capacitance component approaches zero is lower than the predetermined temperature ⁇ .
  • step S1217 the information processing device 1110 notifies that the evaluation of the metal powder to be evaluated is good.
  • step S1219 the information processing device 1110 notifies that the evaluation of the metal powder to be evaluated is not good.
  • the metal additive manufacturing apparatus and the information processing apparatus thereof of the present embodiment it is possible to realize an efficient metal additive manufacturing by evaluating whether or not a metal powder to be used is a metal powder requiring low preheating. it can. That is, by lowering the preheating temperature, the overall lamination molding time is shortened, productivity is improved, and by lowering the preheating temperature, unnecessary powder removal after lamination molding is facilitated.
  • the present invention may be applied to a system including a plurality of devices, or may be applied to a single device. Further, the present invention is also applicable to a case where an information processing program for realizing the functions of the embodiments is directly or remotely supplied to a system or an apparatus. Therefore, in order to implement the functions of the present invention on a computer, a program installed in the computer, a medium storing the program, and a WWW (World Wide Web) server for downloading the program are also included in the scope of the present invention. . In particular, at least a non-transitory computer-readable medium storing a program for causing a computer to execute the processing steps included in the above-described embodiments is included in the scope of the present invention.

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Abstract

The present invention makes it possible to evaluate whether a metal powder is a powder for metal additive manufacturing that does not cause smoke to be emitted even when a preheating temperature is lowered. This evaluation method for a powder for metal additive manufacturing includes: an impedance measurement step in which the impedance of a metal powder is measured while heating the metal powder; a capacitive component extraction step for extracting the capacitive component from the measured impedance; and an evaluation step in which when the capacitive component becomes zero before the metal powder reaches a predetermined temperature, the metal powder is evaluated to be a powder material for metal additive manufacturing that does not cause smoke to be emitted when irradiated with an electron beam even when the preheating temperature of the metal powder is lowered.

Description

金属積層造形用粉末の評価方法、評価プログラムおよび製造方法、情報処理装置および金属積層造形装置Method for evaluating powder for metal additive manufacturing, evaluation program and manufacturing method, information processing apparatus, and metal additive manufacturing apparatus
　本発明は、金属積層造形用材料に関する。 The present invention relates to a material for metal additive manufacturing.
　上記技術分野において、特許文献１には、金属粉末による３次元積層造形の技術が開示されている。特許文献１においては、合金粉末の電子ビームによる溶融において、事前に合金の融点の５０％から８０％の温度による予備加熱（または予備焼結）が行なわれる。 に お い て In the above technical field, Patent Document 1 discloses a technique of three-dimensional additive manufacturing using metal powder. In Patent Document 1, in melting of an alloy powder by an electron beam, preheating (or presintering) at a temperature of 50% to 80% of the melting point of the alloy is performed in advance.
特開２０１６－０２３３６７号公報JP 2016-023367 A
　上記のように、電子ビーム積層造形においては、チャージアップ対策として金属粉末の予備加熱を行う。この時の予備加熱温度は、できるだけ低いことが望まれる。その理由は、予備加熱温度が高いほど予備加熱時間や造形終了後の冷却時間を要するためである。また、予備加熱温度が高いほど金属粉末同士の結合が強固となり、積層造形後の不要粉末除去が困難となるからである。しかしながら、予備加熱温度を低くし過ぎるとスモーク現象が発生して積層造形自体に失敗してしまう。 (4) As described above, in electron beam additive manufacturing, preheating of the metal powder is performed as a measure against charge-up. It is desired that the preheating temperature at this time be as low as possible. The reason for this is that the higher the preheating temperature, the longer the preheating time and the cooling time after the completion of modeling. Further, the higher the preheating temperature, the stronger the bond between the metal powders, and the more difficult it becomes to remove unnecessary powder after the additive manufacturing. However, if the preheating temperature is too low, a smoke phenomenon occurs and the additive manufacturing itself fails.
　そのため、使用する金属積層造形用材料がスモーク現象を発生させないで予備加熱温度を低くできる材料であることを評価する技術が求められている。 Therefore, there is a need for a technique for evaluating that the material used for additive metal manufacturing is a material that can lower the preheating temperature without causing a smoke phenomenon.
　本発明の目的は、上述の課題を解決する技術を提供することにある。 目的 An object of the present invention is to provide a technique for solving the above-mentioned problem.
　上記目的を達成するため、本発明に係る金属積層造形用粉末の評価方法は、
　金属粉末のインピーダンスを測定するインピーダンス測定ステップと、
　前記測定されたインピーダンスから容量成分を抽出する容量成分抽出ステップと、
　前記金属粉末の前記容量成分がゼロになる場合、電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する評価ステップと、
　を含む。 In order to achieve the above object, the evaluation method of the metal additive manufacturing powder according to the present invention,
An impedance measuring step of measuring the impedance of the metal powder,
Capacitive component extraction step of extracting a capacitive component from the measured impedance,
When the capacity component of the metal powder becomes zero, an evaluation step of evaluating a powder material for metal additive manufacturing that does not cause a smoke phenomenon upon irradiation with an electron beam,
including.
　上記目的を達成するため、本発明に係る金属積層造形用粉末の評価プログラムは、
　金属粉末のインピーダンスを取得するインピーダンス取得ステップと、
　前記取得されたインピーダンスから容量成分を抽出する容量成分抽出ステップと、
　前記金属粉末の前記容量成分がゼロになると判定された場合、電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する評価ステップと、
　をコンピュータに実行させる。 To achieve the above object, the metal additive manufacturing powder evaluation program according to the present invention,
An impedance obtaining step of obtaining the impedance of the metal powder,
A capacitance component extraction step of extracting a capacitance component from the obtained impedance,
When it is determined that the capacitance component of the metal powder becomes zero, an evaluation step of evaluating a metal additive manufacturing powder material that does not cause a smoke phenomenon at the time of electron beam irradiation,
On a computer.
　上記目的を達成するため、本発明に係る情報処理装置は、
　金属粉末のインピーダンスを取得するインピーダンス取得手段と、
　前記取得されたインピーダンスから容量成分を抽出する容量成分抽出手段と、
　前記金属粉末の前記容量成分がゼロになると判定された場合、電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する評価手段と、
　を備える。 In order to achieve the above object, an information processing device according to the present invention includes:
Impedance obtaining means for obtaining the impedance of the metal powder,
Capacitance component extraction means for extracting a capacitance component from the obtained impedance,
When it is determined that the capacitance component of the metal powder becomes zero, an evaluation unit that evaluates to be a powder material for metal additive manufacturing that does not cause a smoke phenomenon upon irradiation with an electron beam,
Is provided.
　上記目的を達成するため、本発明に係る金属積層造形用粉末の製造方法は、
　金属粉末のインピーダンスを測定するインピーダンス測定ステップと、
　前記測定されたインピーダンスから容量成分を抽出する容量成分抽出ステップと、
　前記金属粉末の前記容量成分がゼロになる場合、電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する評価ステップと、
　前記評価ステップにおいて、前記金属積層造形用粉末材料であるとの評価されなかった場合、前記金属粉末に対して金属粉末の衝突を含む機械的処理または金属粉末表面の金属被覆処理を施す表面処理ステップと、
　を含む。 In order to achieve the above object, a method for producing a powder for metal additive manufacturing according to the present invention,
An impedance measuring step of measuring the impedance of the metal powder,
Capacitive component extraction step of extracting a capacitive component from the measured impedance,
When the capacity component of the metal powder becomes zero, an evaluation step of evaluating a powder material for metal additive manufacturing that does not cause a smoke phenomenon upon irradiation with an electron beam,
In the evaluation step, when the metal powder is not evaluated as the metal additive manufacturing powder material, a surface treatment step of performing a mechanical treatment including collision of the metal powder on the metal powder or a metal coating treatment on the surface of the metal powder. When,
including.
　上記目的を達成するため、本発明に係る金属積層造形装置は、
　敷き詰めた金属粉末を電子ビームにより選択的に溶解および凝固させて金属積層造形物を造形する金属積層造形装置であって、
　測定された前記金属粉末のインピーダンスを取得するインピーダンス取得手段と、
　前記取得されたインピーダンスから容量成分を抽出する容量成分抽出手段と、
　前記金属粉末の前記容量成分がゼロになると判定された場合、電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する評価手段と、
　前記評価手段が前記金属積層造形用粉末材料であると評価した場合に、前記金属粉末を用いて金属積層造形物を造形する積層造形手段と、
　を備える。 In order to achieve the above object, a metal additive manufacturing apparatus according to the present invention includes:
A metal additive manufacturing apparatus for selectively dissolving and solidifying the spread metal powder by an electron beam to form a metal additive product,
Impedance obtaining means for obtaining the measured impedance of the metal powder,
Capacitance component extraction means for extracting a capacitance component from the obtained impedance,
When it is determined that the capacitance component of the metal powder becomes zero, an evaluation unit that evaluates to be a powder material for metal additive manufacturing that does not cause a smoke phenomenon upon irradiation with an electron beam,
When the evaluating means evaluates the metal additive manufacturing powder material, a laminate modeling means for modeling a metal additive model using the metal powder,
Is provided.
　上記目的を達成するため、本発明に係る情金属積層造形装置の制御プログラムは、
　敷き詰めた金属粉末を電子ビームにより選択的に溶解および凝固させて金属積層造形物を造形する金属積層造形装置の制御プログラムであって、
　測定された前記金属粉末のインピーダンスを取得するインピーダンス取得ステップと、
　前記取得されたインピーダンスから容量成分を抽出する容量成分抽出ステップと、
　前記金属粉末の前記容量成分がゼロになると判定された場合、電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する評価ステップと、
　前記評価ステップにおいて前記金属積層造形用粉末材料であると評価した場合に、前記金属粉末を用いて金属積層造形物を造形する積層造形ステップと、
　をコンピュータに実行させる。 In order to achieve the above object, a control program for an information metal additive manufacturing apparatus according to the present invention includes:
A control program of a metal additive manufacturing apparatus for selectively melting and solidifying the spread metal powder with an electron beam to form a metal additive manufacturing object,
Impedance acquisition step of acquiring the measured impedance of the metal powder,
A capacitance component extraction step of extracting a capacitance component from the obtained impedance,
When it is determined that the capacitance component of the metal powder becomes zero, an evaluation step of evaluating a metal additive manufacturing powder material that does not cause a smoke phenomenon at the time of electron beam irradiation,
In the evaluation step, when it is evaluated that the metal additive manufacturing powder material, the additive manufacturing step of modeling the metal additive using the metal powder,
On a computer.
　本発明によれば、予備加熱温度を低下させてもスモーク現象が発生しない金属積層造形用粉末であると評価することができる。 According to the present invention, it can be evaluated as a powder for metal additive manufacturing that does not cause a smoke phenomenon even when the preheating temperature is lowered.
本発明の実施形態に係る金属積層造形用粉末の製造処理手順を示すフローチャートである。It is a flowchart which shows the manufacturing processing procedure of the powder for metal additive manufacturing according to the embodiment of the present invention. 本発明の実施形態に係る金属粉末の評価処理の手順を示すフローチャートである。It is a flowchart which shows the procedure of the evaluation process of the metal powder which concerns on embodiment of this invention. 本発明の実施形態に係る金属粉末の評価基準を説明する図である。It is a figure explaining the evaluation standard of the metal powder concerning the embodiment of the present invention. 本発明の第１実施例に係る機械的予備処理後の金属粉末を示す図である。FIG. 4 is a view showing a metal powder after a mechanical pretreatment according to the first embodiment of the present invention. 本発明の第１実施例に係る機械的予備処理後の金属粉末の表面像（ＳＥＭ）を示す図である。FIG. 3 is a view showing a surface image (SEM) of the metal powder after the mechanical pretreatment according to the first example of the present invention. 本発明の第１実施例に係る機械的予備処理後の金属粉末の表面分析結果（ＸＰＳ）を示す図である。FIG. 4 is a view showing a surface analysis result (XPS) of the metal powder after the mechanical pretreatment according to the first example of the present invention. 本発明の第１実施例に係る機械的予備処理後の金属粉末の抵抗値の温度変化を示す図である。It is a figure which shows the temperature change of the resistance value of the metal powder after the mechanical pre-processing concerning 1st Example of this invention. 本発明の第１実施例に係る金属粉末の抵抗値を測定した粉末電気抵抗測定装置を示す図である。FIG. 2 is a view illustrating a powder electric resistance measuring device for measuring a resistance value of a metal powder according to a first embodiment of the present invention. 本発明の第１実施例に係る金属粉末の抵抗値を測定した粉末電気抵抗測定治具と温度パターンとを示す図である。It is a figure which shows the electric resistance measurement jig | tool which measured the resistance value of the metal powder concerning 1st Example of this invention, and a temperature pattern. 本発明の第１実施例に係る金属粉末の抵抗値を測定した粉末電気抵抗測定原理を説明する図である。FIG. 3 is a view for explaining the principle of measuring the electric resistance of a powder obtained by measuring the resistance of a metal powder according to the first embodiment of the present invention. 本発明の第１実施例に係る金属粉末の抵抗値を測定した測定接続と測定回路を示す図である。FIG. 4 is a diagram illustrating a measurement connection and a measurement circuit for measuring a resistance value of a metal powder according to the first example of the present invention. 本発明の第１実施例に係る機械的予備処理後の金属粉末のインピーダンスの変化を示す図である。FIG. 4 is a diagram illustrating a change in impedance of the metal powder after the mechanical pretreatment according to the first example of the present invention. 本発明の第１実施例に係る機械的予備処理後の金属粉末のインピーダンスから求めた容量成分の変化を示す図である。FIG. 4 is a diagram illustrating a change in a capacitance component obtained from the impedance of the metal powder after the mechanical pretreatment according to the first example of the present invention. 本発明の第１実施例に係る金属粉末のインピーダンスを測定した粉末電気抵抗測定原理を説明する図である。FIG. 3 is a view for explaining the principle of measuring the electrical resistance of the powder obtained by measuring the impedance of the metal powder according to the first embodiment of the present invention. 本発明の第１実施例に係る金属粉末のインピーダンスを測定した測定接続と測定回路を示す図である。FIG. 4 is a diagram illustrating a measurement connection and a measurement circuit for measuring the impedance of the metal powder according to the first example of the present invention. 本発明の第１実施例に係る機械的予備処理後の金属粉末によるスモークテストの結果を示す図である。It is a figure showing the result of the smoke test with the metal powder after the mechanical pretreatment concerning a 1st example of the present invention. 本発明の第１実施例に係る機械的予備処理後の金属粉末によるスモークテスト方法を説明する図である。It is a figure explaining the smoke test method by the metal powder after the mechanical pretreatment concerning the 1st example of the present invention. 本発明の第１実施例に係る機械的予備処理を行ったジェットミルの原理を示す図である。It is a figure showing the principle of the jet mill which performed mechanical pretreatment concerning a 1st example of the present invention. 本発明の第２実施例に係る機械的予備処理後の金属粉末の表面像（ＳＥＭ）を示す図である。It is a figure which shows the surface image (SEM) of the metal powder after the mechanical pre-processing concerning 2nd Example of this invention. 本発明の第２実施例に係る機械的予備処理後の金属粉末のインピーダンスの変化を示す図である。It is a figure showing change of impedance of metal powder after mechanical pretreatment concerning a 2nd example of the present invention. 本発明の第２実施例に係る機械的予備処理を行ったボールミルおよびその原理を示す図である。It is a figure which shows the ball mill which performed the mechanical pre-processing concerning 2nd Example of this invention, and its principle. 本発明の第３実施例に係る表面被覆処理後の金属粉末の表面像（ＳＥＭ）を示す図である。It is a figure which shows the surface image (SEM) of the metal powder after the surface coating process which concerns on the 3rd Example of this invention. 本発明の第３実施例に係る表面被覆処理後の金属粉末の表面分析結果（ＸＰＳ）を示す図である。It is a figure which shows the surface analysis result (XPS) of the metal powder after the surface coating process which concerns on the 3rd Example of this invention. 本発明の第３実施例に係る表面被覆処理後の金属粉末の抵抗値の温度変化を示す図である。It is a figure showing the temperature change of the resistance value of metal powder after surface coating processing concerning a 3rd example of the present invention. 本発明の第３実施例に係る表面被覆処理後の金属粉末のインピーダンスの変化を示す図である。It is a figure showing change of impedance of metal powder after surface coating processing concerning a 3rd example of the present invention. 本発明の第３実施例に係る表面被覆処理後の金属粉末によるスモークテストの結果を示す図である。It is a figure showing the result of the smoke test with the metal powder after surface coating processing concerning a 3rd example of the present invention. 本発明の実施形態で使用可能な合金粉末の例を示す図である。It is a figure showing an example of the alloy powder which can be used in an embodiment of the present invention. 本発明の実施形態に係る金属積層造形装置の構成を示すブロック図である。It is a block diagram showing composition of a metal additive manufacturing device concerning an embodiment of the present invention. 本発明の実施形態に係る金属積層造形装置の情報処理装置の表示例を示す図である。It is a figure showing the example of a display of the information processor of the metal additive manufacturing device concerning the embodiment of the present invention. 本発明の実施形態に係る金属積層造形装置の情報処理装置の処理手順を示すフローチャートである。It is a flowchart which shows the processing procedure of the information processing apparatus of the metal additive manufacturing apparatus which concerns on embodiment of this invention. 本発明の第２実施例に係る機械的予備処理を行ったボールミルおよびその動作条件を示す図である。It is a figure which shows the ball mill which performed the mechanical pre-processing concerning 2nd Example of this invention, and its operating conditions. 本発明の第２実施例に係る機械的予備処理前後の金属粉末（インコネル718/IN718）の表面像（ＳＥＭ）を示す図である。It is a figure which shows the surface image (SEM) of the metal powder (Inconel 718 / IN718) before and after the mechanical pretreatment concerning the 2nd Example of this invention. 本発明の第２実施例に係る機械的予備処理後の金属粉末（インコネル718/IN718）の抵抗値の温度変化およびインピーダンスの温度変化を示す図である。It is a figure which shows the temperature change of the resistance value and the temperature change of the impedance of the metal powder (Inconel 718 / IN718) after the mechanical pretreatment concerning the 2nd Example of this invention. 本発明の第２実施例に係る機械的予備処理後の金属粉末（インコネル718/IN718）のインピーダンスから求めた容量成分の変化を示す図である。It is a figure showing change of the capacity ingredient calculated from the impedance of metal powder (Inconel 718 / IN718) after mechanical pretreatment concerning a 2nd example of the present invention. 本発明の第２実施例に係る機械的予備処理後の金属粉末（インコネル718/IN718）のＸＰＳ分析結果を示す図である。It is a figure which shows the XPS analysis result of the metal powder (Inconel 718 / IN718) after the mechanical pre-processing concerning 2nd Example of this invention. 本発明の第２実施例に係る機械的予備処理前後の金属粉末（チタン64/Ti64）の表面像（ＳＥＭ）を示す図である。It is a figure which shows the surface image (SEM) of the metal powder (titanium 64 / Ti64) before and after the mechanical pre-processing concerning 2nd Example of this invention. 本発明の第２実施例に係る機械的予備処理後の金属粉末（チタン64/Ti64）の抵抗値の温度変化およびインピーダンスの温度変化を示す図である。It is a figure which shows the temperature change of the resistance value of a metal powder (titanium 64 / Ti64), and the temperature change of an impedance after the mechanical pre-processing concerning 2nd Example of this invention. 本発明の第２実施例に係る機械的予備処理後の金属粉末（チタン64/Ti64）のＸＰＳ分析結果を示す図である。It is a figure which shows the XPS analysis result of the metal powder (titanium 64 / Ti64) after the mechanical pre-processing concerning 2nd Example of this invention. 本発明の第２実施例に係る機械的予備処理前後の金属粉末（チタンアルミニウム合金/TiAl）の表面像（ＳＥＭ）を示す図である。It is a figure which shows the surface image (SEM) of the metal powder (titanium aluminum alloy / TiAl) before and after the mechanical pretreatment concerning the 2nd Example of this invention. 本発明の第２実施例に係る機械的予備処理後の金属粉末（チタンアルミニウム合金/TiAl）の抵抗値の温度変化およびインピーダンスの温度変化を示す図である。It is a figure which shows the temperature change of the resistance value and the temperature change of impedance of the metal powder (titanium aluminum alloy / TiAl) after the mechanical pre-processing concerning 2nd Example of this invention. 本発明の第２実施例に係る機械的予備処理後の金属粉末（チタンアルミニウム合金/TiAl）のＸＰＳ分析結果を示す図である。It is a figure which shows the XPS analysis result of the metal powder (titanium aluminum alloy / TiAl) after the mechanical pre-processing concerning 2nd Example of this invention. 本発明の第２実施例に係る機械的予備処理前後の金属粉末（銅粉末/Cu）の表面像（ＳＥＭ）を示す図である。It is a figure which shows the surface image (SEM) of the metal powder (copper powder / Cu) before and after the mechanical pre-processing concerning 2nd Example of this invention. 本発明の第２実施例に係る機械的予備処理後の金属粉末（銅粉末/Cu）の抵抗値の温度変化およびインピーダンスの温度変化を示す図である。It is a figure which shows the temperature change of the resistance value of the metal powder (copper powder / Cu), and the temperature change of an impedance after the mechanical pre-processing concerning 2nd Example of this invention. 本発明の第２実施例に係る機械的予備処理を行ったボールミルおよびその異なる時間の動作条件を示す図である。It is a figure which shows the ball mill which performed the mechanical pre-processing which concerns on the 2nd Example of this invention, and the operating conditions of the different time. 本発明の第２実施例に係る異なる時間の機械的予備処理前後の金属粉末（インコネル718/IN718）の表面像（ＳＥＭ）を示す図である。It is a figure which shows the surface image (SEM) of the metal powder (Inconel 718 / IN718) before and after the mechanical pre-processing for different time which concerns on the 2nd Example of this invention. 本発明の第２実施例に係る適切な時間を超えた機械的予備処理後の金属粉末（インコネル718/IN718）の状態を示す図である。It is a figure which shows the state of the metal powder (Inconel 718 / IN718) after the mechanical pre-processing beyond the appropriate time which concerns on the 2nd Example of this invention. 本発明の第２実施例に係る異なる時間の機械的予備処理後の金属粉末（インコネル718/IN718）の抵抗値の温度変化を示す図である。It is a figure which shows the temperature change of the resistance value of the metal powder (Inconel 718 / IN718) after the mechanical pre-processing for the different time which concerns on the 2nd Example of this invention. 本発明の第２実施例に係る異なる時間の機械的予備処理後の金属粉末（インコネル718/IN718）のインピーダンスの温度変化を示す図である。It is a figure which shows the temperature change of the impedance of the metal powder (Inconel 718 / IN718) after the mechanical pre-processing for the different time which concerns on the 2nd Example of this invention. 本発明の第２実施例に係る機械的予備処理後の金属粉末によるスモークテストの結果を示す図である。It is a figure showing the result of the smoke test with the metal powder after the mechanical pretreatment concerning a 2nd example of the present invention. 本発明の第２実施例に係る機械的予備処理後の金属粉末によるスモークテスト方法を説明する図である。It is a figure explaining the smoke test method by metal powder after mechanical pretreatment concerning a 2nd example of the present invention. 本発明の第２実施例に係る機械的予備処理後の金属粉末によるスモークテスト条件を示す図である。It is a figure showing the smoke test conditions by the metal powder after the mechanical pretreatment concerning a 2nd example of the present invention.
　以下に、図面を参照して、本発明の実施の形態について例示的に詳しく説明する。ただし、以下の実施の形態に記載されている構成要素は単なる例示であり、本発明の技術範囲をそれらのみに限定する趣旨のものではない。 Hereinafter, embodiments of the present invention will be illustratively described in detail with reference to the drawings. However, the components described in the following embodiments are merely examples, and are not intended to limit the technical scope of the present invention thereto.
　［本実施形態の金属積層造形用粉末の評価方法］
　図１Ａ乃至図２を参照して、本実施形態の金属積層造形用粉末の評価方法を説明する。 [Evaluation Method of Metal Additive Manufacturing Powder of Present Embodiment]
With reference to FIGS. 1A and 2, an evaluation method of the powder for metal additive manufacturing according to the present embodiment will be described.
　《金属積層造形用粉末の処理手順》
　図１Ａは、本実施形態に係る金属積層造形用粉末の製造処理手順を示すフローチャートである。 《Procedure for processing powder for metal additive manufacturing》
FIG. 1A is a flowchart illustrating a manufacturing procedure of the metal additive manufacturing powder according to the present embodiment.
　図１Ａでは、ステップＳ１０１において、評価対象の金属粉末の評価処理を行う。ステップＳ１０３において、評価結果から評価が良好であるか否かを判定する。金属粉末の評価結果が良好（ＹＥＳ）であれば、製造処理手順を終了する。一方、金属粉末の評価結果が良好でない（ＮＯ）の場合は、ステップＳ１０５において、金属粉末の表面処理、特に表面の酸化物に対する処理を行う。 In FIG. 1A, in step S101, an evaluation process is performed on a metal powder to be evaluated. In step S103, it is determined from the evaluation result whether the evaluation is good. If the evaluation result of the metal powder is good (YES), the manufacturing processing procedure ends. On the other hand, when the evaluation result of the metal powder is not good (NO), the surface treatment of the metal powder, in particular, the treatment of the surface oxide is performed in step S105.
　（金属粉末の評価処理）
　図１Ｂは、本実施形態に係る金属粉末の評価処理（Ｓ１０１）の手順を示すフローチャートである。 (Evaluation of metal powder)
FIG. 1B is a flowchart showing the procedure of the metal powder evaluation process (S101) according to the present embodiment.
　図１Ｂで、ステップＳ１１１において、評価対象の金属粉末のインピーダンスを測定する。あるいは、金属粉末の温度を変化させながら測定する。この場合の温度変化は、常温→８００℃に漸次に上昇→温度維持→常温に漸次に下降とする。ステップＳ１１３において、測定されたインピーダンスに基づいて、金属粉末の等価回路により容量成分を算出する。そして、ステップＳ１１５において、算出した容量成分がゼロに近付く温度が所定温度αより低いか否かを判定する。所定温度αは、例えば、２００℃や４００℃が目安である。 In FIG. 1B, in step S111, the impedance of the metal powder to be evaluated is measured. Alternatively, the measurement is performed while changing the temperature of the metal powder. In this case, the temperature change is gradually increased from normal temperature to 800 ° C. → temperature maintained → gradually decreased to normal temperature. In step S113, a capacitance component is calculated by an equivalent circuit of the metal powder based on the measured impedance. Then, in step S115, it is determined whether or not the temperature at which the calculated capacity component approaches zero is lower than a predetermined temperature α. The predetermined temperature α is, for example, 200 ° C. or 400 ° C. as a standard.
　ステップＳ１１５の判定で、容量成分がゼロに近付く温度が所定温度αより低い場合、ステップＳ１１７において、評価対象の金属粉末が比較的低い予備加熱でもスモーク現象が発生しない良好な金属積層造形用粉末と判定する。一方、容量成分がゼロに近付く温度が所定温度αより高い場合、ステップＳ１１９において、評価対象の金属粉末がスモーク現象を発生させないためには比較的高い予備加熱が必要な良好でない金属積層造形用粉末と判定する。 If it is determined in step S115 that the temperature at which the capacitance component approaches zero is lower than the predetermined temperature α, in step S117, the metal powder to be evaluated is a good metal additive manufacturing powder that does not cause a smoke phenomenon even with relatively low preliminary heating. judge. On the other hand, when the temperature at which the capacitance component approaches zero is higher than the predetermined temperature α, in step S119, the poor metal additive manufacturing powder that requires relatively high preheating to prevent the metal powder to be evaluated from generating a smoke phenomenon. Is determined.
　《金属粉末の評価基準》
　図２は、本実施形態に係る金属粉末の評価基準を説明する図である。以下、金属粉末の評価基準について、詳細に説明する。 《Evaluation criteria for metal powder》
FIG. 2 is a diagram illustrating evaluation criteria for the metal powder according to the present embodiment. Hereinafter, the evaluation criteria for the metal powder will be described in detail.
　（金属積層造形プロセス）
　金属積層造形プロセスは、以下の粉末床形成プロセスと、予備加熱と選択的溶融プロセスと、未溶融粉末回収プロセスと、に大別される。 (Metal additive manufacturing process)
Metal additive manufacturing processes are broadly classified into the following powder bed forming processes, preheating and selective melting processes, and unmelted powder recovery processes.
＜粉末床形成プロセス＞
　未溶融欠陥などを作らない造形を行うための最も基本となるプロセスである。そのためには使用する金属粉末の形状は真球に近いもので、かつ粉末表面にサテライトの無い物が求められる。サテライトを有する異形状粉末では流動性が悪いため、粉末床（パウダーベッド）厚さが凸凹になり溶融池（メルトプール）が安定せず、凝固欠陥形成の原因となる。現状の電子ビーム積層造形法では粒度分布として40～100μm程度の粉末が使用されているが、造形物の表面粗さの改善効果を期待して、10～50μm程度のより細かな粒度分布の粉末を使用することも検討されている。 <Powder bed formation process>
This is the most basic process for performing modeling without creating unmelted defects. For that purpose, it is required that the shape of the metal powder used is close to a true sphere and that the powder surface has no satellite. The irregular shape powder having satellites has poor fluidity, so that the thickness of the powder bed (powder bed) becomes uneven, and the molten pool (melt pool) becomes unstable, which causes formation of solidification defects. In the current electron beam additive manufacturing method, powder with a particle size distribution of about 40 to 100 μm is used, but powder with a finer particle size distribution of about 10 to 50 μm is expected in order to improve the surface roughness of the molded article. The use of is also being considered.
＜予備加熱と選択的溶融プロセス＞
　電子ビーム積層造形ではパウダーベッドの溶融プロセスの前にパウダーベッドの予備加熱を行なう、ホットプロセス（hot process）が基本である。これは、電子ビームを加熱されていないパウダーベッドに照射すると粉末が飛散して煙状に舞い上がり（“スモーク”と呼ばれている）、パウダーベッドが消失欠損するため、正常な造形ができなくなるためである。金属粉末表面には酸化被膜が形成されており、電子ビームの負電荷を蓄えることが可能なコンデンサ（キャパシタ）の働きをする。また、その酸化被膜の電気抵抗は室温では高いが、温度上昇とともに低下する半導体的性質を示すと考えられる。 <Preheating and selective melting process>
Electron beam additive manufacturing is based on a hot process in which the powder bed is preheated before the powder bed melting process. This is because when an electron beam is applied to an unheated powder bed, the powder scatters and soars into smoke (called "smoke"), and the powder bed disappears and is lost, preventing normal modeling. It is. An oxide film is formed on the surface of the metal powder, and functions as a capacitor (capacitor) that can store negative charges of the electron beam. The electrical resistance of the oxide film is high at room temperature, but it is considered that the oxide film exhibits semiconductor properties that decrease with increasing temperature.
　このため、電子ビームを室温で電気抵抗が高い状態のパウダーベットに照射すると、粉末粒子間の電子の移動は阻害されるため個々の粉末粒子は酸化被膜のキャパシタ効果によって負に帯電し、粉末同士がクーロン斥力により煙状に“飛散”する。これがスモークの起こるメカニズムと考えられる。このため、電子ビーム積層造形プロセスではパウダーベッドの個々の粉末表面の酸化被膜の電気抵抗が金属的な値になる温度まで加熱する必要がある。予備加熱温度として、金属粉末によって異なるが、おおよそ600～1100℃の間で予備加熱が行なわれ、その後、溶融プロセスに移ることができる。 For this reason, when an electron beam is irradiated on a powder bed at room temperature with a high electrical resistance, the movement of electrons between the powder particles is hindered. Are "splattered" like smoke by Coulomb repulsion. This is thought to be the mechanism by which smoke occurs. Therefore, in the electron beam additive manufacturing process, it is necessary to heat the powder bed to a temperature at which the electrical resistance of the oxide film on the surface of each powder becomes a metallic value. Although the preheating temperature varies depending on the metal powder, the preheating is performed at a temperature of approximately 600 to 1100 ° C., and the process can then proceed to the melting process.
＜未溶融粉末回収プロセス＞
　電子ビーム積層造形では上述したように予備加熱温度に保持されたまま造形が行われるため、未溶融部の粉末が焼結によって弱く結合（焼結）する。造形が終了すると造形物は焼結したパウダーベッドに埋もれたまま取り出される。焼結したパウダーベッドは、サンドブラストの要領で、圧縮空気を用いて造形物の原料粉末をブラスト粒子として高速で吹き付けることで完全に粉砕され、原料粉末の状態に戻すことができる。しかし、予備加熱温度が高すぎると造形中に個々の粉末の接触部が部分的に溶融して強固な結合部が形成され、上述したブラスト処理によるパウダーベッドの粉砕が困難となり、原料粉末の状態に戻すことができなくなる。このような場合は、粉末の再利用ができなくなるだけではなく、造形物と未溶融粉末との分離ができなくなるため部品製造が失敗に終わるこことを意味する。 <Unmelted powder recovery process>
In the electron beam additive manufacturing, since the shaping is performed while being maintained at the preheating temperature as described above, the powder in the unmelted portion is weakly bonded (sintered) by sintering. When the shaping is completed, the shaped object is taken out while being buried in the sintered powder bed. The sintered powder bed is completely pulverized by blowing the raw material powder of the molded article as blast particles at high speed using compressed air in the manner of sand blasting, and can be returned to the state of the raw material powder. However, if the preheating temperature is too high, the contact portions of the individual powders are partially melted during molding to form a strong bonding portion, and it becomes difficult to pulverize the powder bed by the above-mentioned blast treatment, and the state of the raw material powder Can not be returned to. In such a case, not only the powder cannot be reused, but also it becomes impossible to separate the molded object and the unmelted powder, so that the part production ends in failure.
　ここで、電子ビーム積層造形では、予備加熱温度が高い合金粉末の場合はパウダーベッドの結合固化の進行が問題となる場合があるが、予備加熱により造形物中に発生する熱応力による残留ひずみが少なくなるため、造形物の反り・変形、内部き裂の発生が抑制される。このため、電子ビーム積層造形ではサポート数を最小限に抑えることが可能となる。このように、予備加熱は造形物の材質や形状制御の際に利点として効果を発揮し、金属間化合物のような延性に乏しい材料の造形にはホットプロセスを採用する電子ビーム積層造形が有利となる。 Here, in electron beam additive manufacturing, in the case of an alloy powder having a high preheating temperature, progress of solidification of the powder bed may be a problem, but residual strain due to thermal stress generated in the formed object by preheating is problematic. Since the number is reduced, warpage and deformation of the modeled object and generation of internal cracks are suppressed. Therefore, in the electron beam additive manufacturing, the number of supports can be minimized. As described above, the preheating is effective as an advantage in controlling the material and shape of the formed object, and the electron beam additive manufacturing employing the hot process is advantageous in forming the material having poor ductility such as an intermetallic compound. Become.
　（電子ビームと金属粉体との相互作用）
　金属は電気的には良導体であり、電子ビームが照射される際アースがとられていれば（負に）帯電することはないため、金属バルクは電子ビーム照射が連続的に可能であり溶融させることができる。一方、電子ビーム積層造形法では、粒径が40～150μm程度の大きさに分布するパウダーベットに電子ビームを照射するため、溶融プロセスは単純ではない。後述するように、金属粉末床の電気抵抗率を室温で測定すると107Ωm以上のオーダーの値となる。これは、上述したように金属粉末表面に酸化被膜が形成されており、その多くは電気的には半導体的に振る舞うため、室温での粉体同士の接触抵抗が高いためと考えられる。その堆積物であるパウダーベッドの電気抵抗も金属的というよりは、半導体的に振る舞うと考えられる。 (Interaction between electron beam and metal powder)
Metals are electrically good conductors, and if they are grounded when irradiated with an electron beam, they will not be charged (negatively), so the metal bulk can be continuously irradiated with the electron beam and melted be able to. On the other hand, in the electron beam additive manufacturing method, the melting process is not simple because an electron beam is applied to a powder bed having a particle size distribution of about 40 to 150 μm. As will be described later, when the electrical resistivity of the metal powder bed is measured at room temperature, the value is on the order of 107 Ωm or more. This is considered to be because the oxide film is formed on the surface of the metal powder as described above, and most of them behave electrically as a semiconductor, so that the contact resistance between the powders at room temperature is high. It is considered that the electric resistance of the powder bed, which is the deposit, behaves more like a semiconductor than a metallic one.
　このため、電子ビームをパウダーベットに照射すると、個々の粉末粒子は負に帯電（チャージアップ）し、粉末同士はクーロン斥力により煙状に“飛散”する現象が生じる。正確には照射電子ビームの周囲に照射方向に垂直に磁場が形成されているため、負に帯電した粉末粒子が磁場中でクーロン斥力により運動し始め、ローレンツ力により大規模な粉末床の“飛散現象（スモーク）”が生じるものと考えられる。前述したように、実際の造形プロセスでは電子ビーム溶融照射を行う前に700℃以上の温度に粉末床の予熱を行うことでスモークを回避している。これは、前述したように金属粉末表面の酸化被膜は半導体的に振る舞うため、温度上昇により電気抵抗が低下するため高温になるほど粉末同士の接触抵抗が低下し、パウダーベットに金属的な電気伝導が起きるようになるためと考えられる。さらに、スモーク現象を回避するための予熱温度が高すぎると、造形中に個々の粉末の接触部分での部分溶融が進行してパウダーベッドの固化が進行し溶融部分と未溶融部分との分離が困難になり、造形上の障害となるので注意が必要である。 Therefore, when an electron beam is applied to the powder bed, the individual powder particles are negatively charged (charged up), and the powders "splatter" like smoke due to Coulomb repulsion. Precisely, since a magnetic field is formed around the irradiation electron beam perpendicular to the irradiation direction, the negatively charged powder particles begin to move in the magnetic field due to Coulomb repulsion, and the “scattering” of a large-scale powder bed by Lorentz force It is considered that a phenomenon (smoke) occurs. As described above, in the actual molding process, smoke is avoided by preheating the powder bed to a temperature of 700 ° C. or more before performing the electron beam fusion irradiation. This is because, as described above, the oxide film on the surface of the metal powder behaves like a semiconductor, and the electrical resistance decreases as the temperature rises. It is thought to be to get up. Furthermore, if the preheating temperature for avoiding the smoke phenomenon is too high, the partial melting at the contact portions of the individual powders proceeds during molding, the solidification of the powder bed progresses, and the separation of the molten and unmelted portions occurs. Care must be taken because it becomes difficult and hinders the modeling.
　（パウダーベッドの電気的特性とスモーク発生挙動）
　電子ビーム積層造形では予備加熱が無い場合、あるいは予備加熱があっても加熱温度が高くない場合は、電子ビーム照射により粉末床の溶融プロセスの前に合金粉末が飛散するスモーク現象が起こる。これは、合金粉末の表面酸化被膜の接触抵抗により電子の流れが阻害される結果起こる現象であると考えられるが、実際に表面酸化被膜の電気的挙動を調べることにより、スモーク現象が生起するメカニズムを検証する必要がある。 (Electrical characteristics of powder bed and smoke generation behavior)
In the case of the electron beam additive manufacturing, when there is no preheating, or when the heating temperature is not high even with the preheating, a smoke phenomenon occurs in which the alloy powder is scattered by the electron beam irradiation before the melting process of the powder bed. This is considered to be a phenomenon that occurs as a result of obstruction of the flow of electrons due to the contact resistance of the surface oxide film of the alloy powder. By actually examining the electrical behavior of the surface oxide film, the mechanism by which the smoke phenomenon occurs Need to be verified.
　合金粉末の直流電気抵抗率の温度依存性
　直流四端子法で測定された室温から800℃までの昇温過程と降温過程での電気抵抗率の変化を測定すると、合金粉末の種類により昇温過程では室温付近での抵抗率の値に違いが生じるが、昇温と共に急激に電気抵抗率の値が低下し、酸化物（半導体）的な電気抵抗の温度依存性を示し、500～600℃で10-4Ωmのオーダーの抵抗率となる。それ以上の温度では800℃までほとんど温度依存性が消失する。これは、600℃以上の高温では合金粉末の表面酸化被膜の電気的性質は酸化物から金属的な電気伝導に変化することを示唆している。800℃からの降温過程では電気抵抗率の値は元の値には戻らず室温まで抵抗率の値はほとんど変化せず大きなヒステリシスを示す。これは、粉末表面の酸化被膜の電気的性質が温度上昇に伴い酸化物的から金属的へと変化することを示唆しており、粉末表面に形成されている酸化被膜の熱的安定性は極めて小さいものと推察できる。実際の造形プロセスでは合金粉末は650℃程度での加熱でスモークの発生がなくなり、電子ビーム積層造形が可能となるのはこのように650℃以上の予備加熱によりパウダーベッドの電気伝導が金属的になるためと理解される。 Temperature dependence of DC electrical resistivity of alloy powder.The change in electrical resistivity between the temperature rise process from room temperature to 800 ° C and the temperature drop process measured by the DC four-terminal method was measured. Although the value of resistivity near room temperature changes, the value of electrical resistivity decreases rapidly with increasing temperature, showing the temperature dependence of electrical resistance like an oxide (semiconductor). The resistivity is on the order of 10-4Ωm. At higher temperatures, the temperature dependence almost disappears up to 800 ° C. This suggests that the electrical properties of the surface oxide film of the alloy powder change from oxide to metallic electrical conductivity at a high temperature of 600 ° C or higher. In the process of decreasing the temperature from 800 ° C., the value of the electrical resistivity does not return to the original value, and the value of the resistivity hardly changes to room temperature, showing a large hysteresis. This suggests that the electrical properties of the oxide film on the powder surface change from oxide to metal with increasing temperature, and the thermal stability of the oxide film formed on the powder surface is extremely high. It can be inferred that it is small. In the actual molding process, smoke is eliminated by heating the alloy powder at about 650 ° C, and electron beam additive manufacturing becomes possible as described above. To be understood.
　（合金粉末の交流インピーダンスの温度依存性）
　プラズマアトマイズ法で得られたインコネル718合金粉末の、室温（RT）、50℃、100℃、200℃から100℃間隔で800℃までの温度での交流インピーダンス測定結果（Cole-Cole プロット）によれば、室温から200℃までは半円状のCole-Cole プロットが得られる。半円状のCole-Cole プロットを、図２の式２０２（Cole-Cole緩和型）にフィットさせることで、等価回路と各抵抗成分とキャパシタ成分（容量成分）との温度変化を求めることができる。　
　図２に、例として、室温から200℃までのCole-Coleプロットに式２０２をフィットさせた結果２０３を示している。この図より、実測されたCole-Coleプロットは式２０２に良くフィットすることが分かり、等価回路２０１として、図２に示すように、合金粉末の表面酸化物の抵抗（Ｒoxide）とキャパシタ（Ｃoxide）の並列回路が合金粉末のバルクの電気抵抗（Ｒmetal）と直列に結合した電気回路が得られる。フィッティングによって得られた各抵抗値とキャパシタンスの値を表２０４にまとめて示す。等価回路２０１を用いて電子ビーム照射によるパウダーベッドのスモーク現象を議論する場合、電荷を蓄積するキャパシタの値が大きいものほどパウダーベッドの電荷の蓄積が大きいためスモークし易いと考えられる。反対に、キャパシタの値が小さいものほどスモークが発生し難いと考えられ、等価回路のキャパシタの変化によりスモーク発生挙動を制御することが可能となる。 (Temperature dependence of AC impedance of alloy powder)
According to AC impedance measurement results (Cole-Cole plot) of Inconel 718 alloy powder obtained by the plasma atomization method at room temperature (RT), 50 ℃, 100 ℃, and 200 ℃ to 800 ℃ at 100 ℃ intervals. For example, a semicircle Cole-Cole plot is obtained from room temperature to 200 ° C. By fitting a semi-circle Cole-Cole plot to Equation 202 (Cole-Cole relaxation type) in FIG. 2, it is possible to obtain an equivalent circuit and a temperature change between each resistance component and a capacitor component (capacitance component). .
FIG. 2 shows, as an example, a result 203 obtained by fitting the equation 202 to a Cole-Cole plot from room temperature to 200 ° C. From this figure, it can be seen that the measured Cole-Cole plot fits well to Equation 202, and as an equivalent circuit 201, as shown in FIG. 2, the resistance (R oxide ) of the surface oxide of the alloy powder and the capacitor (C An electrical circuit is obtained in which a parallel circuit of oxide ) is coupled in series with the bulk electrical resistance ( Rmetal ) of the alloy powder. Table 204 collectively shows the resistance values and the capacitance values obtained by the fitting. When discussing the smoke phenomenon of the powder bed caused by the electron beam irradiation using the equivalent circuit 201, it is considered that the larger the value of the capacitor for storing the electric charge, the larger the electric charge of the powder bed is, and thus the easier the smoke is. Conversely, it is considered that the smaller the value of the capacitor is, the more difficult it is for smoke to be generated, and it is possible to control the smoke generation behavior by changing the capacitor of the equivalent circuit.
　一方、300℃以上の温度でのCole-Coleプロットは原点付近に収束し、表面酸化被膜のインピーダンス成分としてＲoxideの抵抗成分が支配的となることが示唆される。この場合の等価回路は、バルクの電気抵抗（Ｒmetal）と合金粉末の表面酸化物の抵抗（Ｒoxide）が直列に結合した回路として表現できる。このことは、パウダーベッドは予備加熱されることによりキャパシタ成分Ｃoxideが消失することを意味しており、パウダーベッドは電荷の蓄積が起こらない電気的構造に変化することを示唆しており、電子ビーム照射してもスモークが発生しないと考えられる。実際の電子ビーム積層造形において、例えば、チタン合金粉末の場合では650℃程度での予備加熱でスモークの発生がなくなるのは、チタン合金粉末のパウダーベッドのキャパシタ成分Ｃoxideが予備加熱により消失するためと解釈できる。上述した直流電気抵抗測定により明らかになったように、粉末表面の酸化被膜は熱的安定性が小さく、これは予備加熱でキャパシタ成分Ｃoxideが消失する要因となると考えられる。 On the other hand, the Cole-Cole plot at a temperature of 300 ° C. or more converges near the origin, suggesting that the resistance component of R oxide is dominant as the impedance component of the surface oxide film. The equivalent circuit in this case can be expressed as a circuit in which the bulk electrical resistance (R metal ) and the resistance (R oxide ) of the surface oxide of the alloy powder are connected in series. This means that the powder bed is preheated, so that the capacitor component C oxide disappears, suggesting that the powder bed changes to an electrical structure in which charge accumulation does not occur. It is considered that smoke is not generated even by beam irradiation. In the actual electron beam additive manufacturing, for example, in the case of titanium alloy powder, the generation of smoke is eliminated by preheating at about 650 ° C. because the capacitor component C oxide of the powder bed of titanium alloy powder disappears by preheating. Can be interpreted as As clarified by the above-described DC electric resistance measurement, the oxide film on the powder surface has low thermal stability, which is considered to be a cause of the disappearance of the capacitor component C oxide by preheating.
　以上のように、合金粉末の電気抵抗測定から得られた知見として、電子ビーム照射によってパウダーベッドが負の電荷に帯電し、スモークが発生するのは、合金粉末表面の酸化被膜に起因するキャパシタ成分Ｃoxideによるものであり、これを消失させることによりスモークの発生を抑制することができる。現状のスモーク回避対策として、パウダーベッドの予備加熱を行っているが、加熱によらないその他の方法によっても、キャパシタ成分Ｃoxideを消失させる方法を実施すれば、その技術は予備加熱以外のスモーク回避法となる。造形プロセス中に発生する造形物の残留応力の除去を目的とする場合は、予備加熱温度は500～600℃で行えば十分目的を達成できると考えられる。したがって、予備加熱以外のキャパシタＣoxideを消失させる技術は従来の予備加熱温度を大幅に低温化できることになり、予備加熱プロセスでのパウダーベッドの粉末の部分溶融結合による固化の問題も生じないことから、電子ビーム積層造形技術の適用範囲を飛躍的に拡大させる。 As described above, as a result obtained from the measurement of the electrical resistance of the alloy powder, the powder bed is charged to a negative charge by electron beam irradiation, and smoke is generated due to the capacitor component caused by the oxide film on the surface of the alloy powder. This is due to C oxide, and by eliminating this, the generation of smoke can be suppressed. As a current measure to avoid smoke, the powder bed is pre-heated. However, if a method that eliminates the capacitor component C oxide is also implemented by other methods that do not rely on heating, the technology can avoid smoke other than pre-heat. Be the law. When the purpose is to remove the residual stress of the modeled object generated during the modeling process, it is considered that the purpose can be sufficiently achieved if the preheating temperature is set at 500 to 600 ° C. Therefore, the technology for dissipating the capacitor C oxide other than the preheating can significantly lower the conventional preheating temperature, and does not cause the problem of solidification due to the partial fusion bonding of the powder of the powder bed in the preheating process. The scope of application of electron beam additive manufacturing technology will be dramatically expanded.
　《本実施形態の効果》
　本実施形態によれば、金属粉末のインピーダンスを測定して、容量成分を算出することにより、算出された容量成分の温度依存に基づいて、予備加熱温度を低下させても金属粉末がスモーク現象を発生しない金属粉末であることを評価できる。 << Effect of this embodiment >>
According to the present embodiment, by measuring the impedance of the metal powder and calculating the capacitance component, based on the temperature dependence of the calculated capacitance component, even if the preheating temperature is reduced, the metal powder can cause the smoke phenomenon. It can be evaluated that the metal powder does not generate.
　かかる評価により、予備焼結温度を低下させることが可能となる。例えば、インコネル718粉に機械的予備処理を施した場合、スモーク現象を発生させずに通常の予備加熱温度を１１５０℃から６００～５００℃まで低下させることが可能となった。 With such an evaluation, the pre-sintering temperature can be lowered. For example, when mechanical pretreatment is performed on Inconel 718 powder, it has become possible to lower the normal preheating temperature from 1150 ° C. to 600 to 500 ° C. without generating a smoke phenomenon.
　そして、予備加熱温度を低下させることで全体の積層造形時間が短縮され、生産性が向上すると共に、予備加熱温度が低下することで積層造形後の不要粉末除去が容易となった。 By lowering the preheating temperature, the overall lamination molding time was shortened, productivity was improved, and by lowering the preheating temperature, unnecessary powder removal after lamination molding was facilitated.
　以下、本実施形態に従った実施例１乃至３と、比較例とについて説明する。実施例１は、ジェットミルにより機械的予備処理を施した場合である。実施例２は、ボールミルにより機械的予備処理を施した場合である。実施例３は、金属めっき処理を施した場合である。比較例は、予備処理を施さない場合である。 Hereinafter, Examples 1 to 3 according to this embodiment and a comparative example will be described. Example 1 is a case where a mechanical pretreatment is performed by a jet mill. Example 2 is a case where mechanical pretreatment was performed by a ball mill. Example 3 is a case where a metal plating process is performed. The comparative example is a case where the preliminary treatment is not performed.
　［実施例１］
　《使用した金属粉末》
　本実施例においては、ガスアトマイズ法で生成したニッケル系合金のインコネル718（登録商標）の金属粉末を使用した。図３Ａに、ＳＥＭ(Scanning Electron Microscope)像および粒子径の分布１２０で示している。 [Example 1]
《Used metal powder》
In this example, a nickel-based alloy powder of Inconel 718 (registered trademark) produced by a gas atomizing method was used. FIG. 3A shows an SEM (Scanning Electron Microscope) image and a particle size distribution 120.
　《機械的予備処理》
　合金粉末の機械的予備処理としては、ジェットミルによる機械的予備処理を行った。 《Mechanical pretreatment》
As mechanical pretreatment of the alloy powder, mechanical pretreatment by a jet mill was performed.
　（ジェットミルの装置）
　ジェットミルとしては、日清エンジニアリング株式会社製の気流式粉砕機スーパージェットミル（ＳＪ－１５００）を使用した。圧力は0.65MPa、金属粉末の供給速度は5kg／hrとした。なお、図７にジェットミルの原理図を示す。投入された未機械的処理の金属粉末が、噴射される高圧ガス（図７ではＮ2ガス）で撹拌されて衝突を繰り返す。そして、機械的処理後の金属粉末が排出される。なお、機械的処理中に、金属粉末が１００℃～３００℃に加熱されるのが、容量成分を削減するには望ましい。 (Jet mill equipment)
As a jet mill, an air flow type pulverizer Super Jet Mill (SJ-1500) manufactured by Nisshin Engineering Co., Ltd. was used. The pressure was 0.65 MPa, and the supply rate of the metal powder was 5 kg / hr. FIG. 7 shows a principle diagram of the jet mill. The input non-mechanical treated metal powder is stirred by the injected high-pressure gas (N 2 gas in FIG. 7) and repeats collision. Then, the metal powder after the mechanical treatment is discharged. It is desirable that the metal powder be heated to 100 ° C. to 300 ° C. during the mechanical treatment in order to reduce the capacity component.
　《機械的予備処理後の金属粉末表面の物理的および科学的特性》
　機械的予備処理後の粉末粒子と、機械的予備処理の無い粉末粒子とのＳＥＭ像を観察し、その粒径度分布を調べた。図３ＡにＳＥＭ像および粒径度分布を示す。 《Physical and scientific properties of metal powder surface after mechanical pretreatment》
SEM images of the powder particles after the mechanical pretreatment and the powder particles without the mechanical pretreatment were observed, and the particle size distribution was examined. FIG. 3A shows an SEM image and a particle size distribution.
　図３Ａには、市販品のプラズマアトマイズ法によるインコネル718のＳＥＭ像および粒径度分布１１０と、上記ガスアトマイズ法によるインコネル718のＳＥＭ像および粒径度分布１２０と、機械的予備処理を行った後の、上記ガスアトマイズ法によるインコネル718のＳＥＭ像および粒径度分布１３０と、を対比して示す。 FIG. 3A shows a SEM image and a particle size distribution 110 of Inconel 718 obtained by a commercially available plasma atomizing method, a SEM image and a particle size distribution 120 of Inconel 718 obtained by the gas atomizing method, and after performing a mechanical pretreatment. The SEM image and the particle size distribution 130 of Inconel 718 by the above-mentioned gas atomization method are shown in comparison.
　図３Ａによれば、機械的予備処理により粒子径が平均化しているが、全体のＳＥＭ像および粒径度分布において、予備加熱の低減に繋がると考えられる形状的な差異は見られない。すなわち、機械的予備処理（高速・高圧の気流での攪拌）で微粉が除去されている様子が見られた。また、プラズマアトマイズ粉末と比較すると粉末の形状について球形状では無く若干の変形・端面の発生が見られた。しかし、粒径度分布について、大きな差は見られずほぼ同等に揃っている。 に よ According to FIG. 3A, the particle diameter is averaged by the mechanical pretreatment, but there is no difference in the overall SEM image and the particle size distribution that is considered to lead to a reduction in preheating. That is, it was observed that fine powder had been removed by mechanical pretreatment (stirring with a high-speed, high-pressure gas stream). Further, as compared with the plasma atomized powder, the shape of the powder was not spherical but slightly deformed and an end face was observed. However, there is no large difference in the particle size distribution, and they are almost equal.
　図３Ｂには、機械的予備処理後の粉末粒子の表面の拡大ＳＥＭ像２３０と、機械的予備処理の無い粉末粒子の表面の拡大ＳＥＭ像２１０，２２０と、を対比して示す。 FIG. 3B shows an enlarged SEM image 230 of the surface of the powder particle after the mechanical pretreatment and enlarged SEM images 210 and 220 of the surface of the powder particle without the mechanical pretreatment.
　図３Ｂによれば、拡大ＳＥＭ像２１０，２２０に見られるデンドランド組織（樹枝状結晶）を含む凝固組織が、拡大ＳＥＭ像２３０においては機械的予備処理における粉末粒子の衝突により平坦化されているのが分かる。かかるデンドランド組織を含む凝固組織の平坦化（減少）は、予備加熱の低減に繋がる可能性があると考えられる。すなわち、機械的予備処理前の粉末ではデンドライド組織が見られたが、機械的予備処理後ではデンドライドが見られず表面が平らになっている様子が見られた。したがって、デンドライドの存在が影響を及ぼしている可能性がある。 According to FIG. 3B, the solidified structure including the dendrite structure (dendrites) seen in the enlarged SEM images 210 and 220 is flattened in the enlarged SEM image 230 by the collision of the powder particles in the mechanical pretreatment. I understand. It is considered that the flattening (reducing) of the solidified structure including the dendland structure may lead to a reduction in preheating. That is, the powder before the mechanical pretreatment had a dendritic structure, but after the mechanical pretreatment, no dendrites were observed and the surface was flat. Therefore, the presence of dendrites may have an effect.
　図３Ｃには、機械的予備処理後の粉末粒子の表面のＸＳＰ（Ｘ線光電子分光法：X-ray Photoelectron Spectroscopy）分析結果３３０と、機械的予備処理の無い粉末粒子の表面のＸＳＰ分析結果３１０と、を対比して示す。 FIG. 3C shows an XSP (X-ray photoelectron spectroscopy) analysis result 330 of the surface of the powder particles after the mechanical pretreatment and an XSP analysis result 310 of the surface of the powder particles without the mechanical pretreatment. And are shown in contrast.
　図３Ｃによれば、表面の酸化層についてプラズマアトマイズ粉末と機械的予備処理を実施した粉末で大きな違いは見られず、酸化層の化学的な変化は見られなかった。 According to FIG. 3C, no significant difference was observed between the plasma atomized powder and the powder subjected to the mechanical pretreatment for the oxide layer on the surface, and no chemical change of the oxide layer was observed.
　（物理的および科学的特性の評価）
　図３Ａ乃至図３Ｃの結果から、次のことが想定される。図３Ａから粒径度分布について大きな差は見られなかったこと、図３Ｃから金属粉末表面の酸化層の化学的な変化は見られなかったこと、が分かった。このため、機械的予備処理により表面の酸化層が物理的な影響により変化しており、図３Ｂから明らかなデンドライドの存在が影響していると判断される。 (Evaluation of physical and scientific properties)
From the results of FIGS. 3A to 3C, the following is assumed. From FIG. 3A, it was found that there was no significant difference in the particle size distribution, and from FIG. 3C, it was found that there was no chemical change in the oxide layer on the surface of the metal powder. Therefore, the oxide layer on the surface is changed due to the physical influence due to the mechanical pretreatment, and it is determined that the presence of dendrites, which is apparent from FIG. 3B, is affecting.
　《機械的予備処理後の金属粉末の電気的特性》
　機械的予備処理後の金属粉末の電気的特性として、温度変化に対応した抵抗値（抵抗率）の変化と、インピーダンスの変化を測定した。 《Electrical properties of metal powder after mechanical pretreatment》
As electrical characteristics of the metal powder after the mechanical pretreatment, a change in resistance value (resistivity) corresponding to a change in temperature and a change in impedance were measured.
　（電気抵抗の測定装置）
　本実施例において、金属粉末の電気抵抗を測定した装置は、次の装置である。
・粉末電気抵抗測定装置　ＴＧ２６５９２（株式会社東栄科学産業）
・高温粉末抵抗測定用真空炉　ＴＧ２６６６７（株式会社東栄科学産業）
　図４Ｂ乃至図４Ｅを参照して、本実施例における金属粉末の電気抵抗の測定を説明する。 (Electrical resistance measuring device)
In the present embodiment, the following device measures the electric resistance of the metal powder.
・ Powder electric resistance measurement device TG26592 (Toei Science Industry Co., Ltd.)
・ Vacuum furnace for high temperature powder resistance measurement TG26667 (Toei Kagaku Sangyo Co., Ltd.)
The measurement of the electrical resistance of the metal powder in the present embodiment will be described with reference to FIGS. 4B to 4E.
　図４Ｂは、粉末電気抵抗測定装置４２０を示す図である。粉末電気抵抗測定装置４２０においては、高温粉末抵抗測定用真空炉４３０内に測定対象の金属粉末をセットして電気抵抗を測定する。図４Ｃは、粉末電気抵抗測定治具４４０と温度パターン４５０とを示す図である。測定条件は、例えば、雰囲気圧力：0.01Pa未満、粉末充填筒内径：φ10mm、粉末高さ：10mmである。粉末電気抵抗測定装置４２０は、温度パターン４５０に示すように、金属粉末を室温（ＲＴ）から８００℃に徐々に上げて所定時間保持し、徐々に下げながら電気抵抗を測定する。詳細には、(1)常温から開始し、(2)800℃まで加熱（昇温速度5℃/min）し、(3)800℃で1時間保持し、(4)常温まで冷却（冷却速度5℃/min）する。図４Ｄは、粉末電気抵抗測定装置４２０における測定概要４６０および高温粉末抵抗測定用真空炉４３０内の構造４７０を示す図である。粉末電気抵抗は、ＤＣ抵抗メータにより測定される。図４Ｅは、直流電気抵抗測定接続４８０および直流電気抵抗測定回路図４９０を示す図である。 FIG. 4B is a diagram showing a powder electric resistance measuring device 420. In the powder electric resistance measuring device 420, a metal powder to be measured is set in a high-temperature powder resistance measuring vacuum furnace 430, and electric resistance is measured. FIG. 4C is a diagram showing a powder electric resistance measuring jig 440 and a temperature pattern 450. The measurement conditions are, for example, an atmosphere pressure: less than 0.01 Pa, an inner diameter of the powder-filled cylinder: φ10 mm, and a powder height: 10 mm. As shown in a temperature pattern 450, the powder electric resistance measuring device 420 gradually increases the metal powder from room temperature (RT) to 800 ° C., holds the metal powder for a predetermined time, and measures the electric resistance while gradually lowering the metal powder. Specifically, (1) start from room temperature, (2) heat to 800 ° C (heating rate 5 ° C / min), (3) hold at 800 ° C for 1 hour, (4) cool to room temperature (cooling rate 5 ℃ / min). FIG. 4D is a diagram showing a measurement outline 460 in the powder electric resistance measuring device 420 and a structure 470 in the vacuum furnace 430 for measuring a high-temperature powder resistance. Powder electrical resistance is measured by a DC resistance meter. FIG. 4E shows a DC electrical resistance measurement connection 480 and a DC electrical resistance measurement circuit diagram 490.
　（電気抵抗の測定結果）
　図４Ａは、図４Ｂ乃至図４Ｅに従い測定された電気抵抗の変化を示す図である。 (Measurement result of electric resistance)
FIG. 4A is a diagram showing a change in electric resistance measured according to FIGS. 4B to 4E.
　図４Ａにおいて、金属粉末は室温（ＲＴ）から８００℃に徐々に上がるにしたがって、電気抵抗が低下（導電性が上昇）する。そして、８００℃から常温に冷却しても、電気抵抗（導電性）はほとんど変化しない。これは、金属粉末表面に形成された酸化被膜が熱的に不安定であり、加熱によって安定するためである。 In FIG. 4A, as the metal powder gradually rises from room temperature (RT) to 800 ° C., the electric resistance decreases (the conductivity increases). And even if it cools from 800 degreeC to normal temperature, electric resistance (electric conductivity) hardly changes. This is because the oxide film formed on the surface of the metal powder is thermally unstable and is stabilized by heating.
　そして、図４Ａから明らかなように、機械的予備処理後の金属粉末１３０は、加熱前の常温（ＲＴ）時から一貫して機械的予備処理の無い金属粉末１１０，１２０よりも、電気抵抗が低い（導電性が高い）ので、電子ビームによる焼結性が向上し、短時間で焼結し易くなることにより予備加熱温度を低下することができる。 And, as is clear from FIG. 4A, the metal powder 130 after the mechanical pretreatment has a lower electric resistance than the metal powders 110 and 120 without the mechanical pretreatment consistently at the room temperature (RT) before heating. Since the sintering property is low (high conductivity), the sinterability by the electron beam is improved, and the sintering is easily performed in a short time, so that the preheating temperature can be lowered.
　（インピーダンスの測定装置）
　本実施例において、金属粉末のインピーダンスを測定した装置は、次の装置である。
・粉末交流抵抗測定システム　２９７１０（株式会社東栄科学産業）
・高温粉末抵抗測定用真空炉　ＴＧ２６６６７（株式会社東栄科学産業）
　図５Ｃおよび図５Ｄを参照して、本実施例における金属粉末のインピーダンスの測定を説明する。なお、インピーダンス測定のためのＡＣ／ＬＲＣメータ５７０への結線以外は電気抵抗と同様であるので、図４Ｂ～図４Ｅと同じ構成要素あるいは処理（例えば、温度パターンなど）の説明は省略する。図５Ｄは、交流インピーダンス測定接続５８０および交流インピーダンス測定回路図５９０を示す図である。 (Impedance measuring device)
In this embodiment, the following device measures the impedance of the metal powder.
・ Powder AC Resistance Measuring System 29710
・ Vacuum furnace for high temperature powder resistance measurement TG26667 (Toei Kagaku Sangyo Co., Ltd.)
With reference to FIGS. 5C and 5D, measurement of the impedance of the metal powder in the present example will be described. Since the resistance is the same as the electric resistance except for the connection to the AC / LRC meter 570 for measuring the impedance, the description of the same components or processes (for example, temperature patterns, etc.) as in FIGS. 4B to 4E will be omitted. FIG. 5D shows an AC impedance measurement connection 580 and an AC impedance measurement circuit diagram 590.
　（インピーダンスの測定結果）
　図５Ａは、図５Ｂおよび図５Ｃに従い測定されたインピーダンスの変化を示す図である。図５Ａは、いわゆる、Cole-Coleプロットである。 (Result of impedance measurement)
FIG. 5A is a diagram showing a change in impedance measured according to FIGS. 5B and 5C. FIG. 5A is a so-called Cole-Cole plot.
　機械的予備処理の無いプラズマアトマイズ法の金属粉末のCole-Coleプロット５１０は、２００℃においては、インピーダンスは５桁台（X0000Ω）である。また、拡大プロット５２０によっても、３００℃で３桁台（X00Ω）であり、４００℃を越えて小さな値になる。一方、本実施例の機械的予備処理後のガスアトマイズ法の金属粉末は、１００℃で３桁（100Ω）を切り、２００℃を越えると１桁（XΩ)以下となる。 C The Cole-Cole plot 510 of the metal powder of the plasma atomization method without mechanical pretreatment shows that the impedance is in the order of 5 digits (X0000Ω) at 200 ° C. Further, according to the enlarged plot 520, the value is in the order of three digits (X00Ω) at 300 ° C., and becomes a small value exceeding 400 ° C. On the other hand, the metal powder of the gas atomization method after the mechanical pretreatment of this embodiment cuts three digits (100Ω) at 100 ° C., and becomes one digit (XΩ) or less when the temperature exceeds 200 ° C.
　（容量成分の算出結果）
　図５Ｂは、図５Ａのインピーダンス測定結果から、等価回路モデル５４０により算出した容量成分の算出結果である。図５Ｂは、機械的予備処理の無いプラズマアトマイズ法の金属粉末の容量成分５５０と、本実施例の機械的予備処理後のガスアトマイズ法の金属粉末の容量成分５６０と、を示している。 (Calculation result of capacitance component)
FIG. 5B is a calculation result of the capacitance component calculated by the equivalent circuit model 540 from the impedance measurement result of FIG. 5A. FIG. 5B shows a capacity component 550 of the metal powder of the plasma atomization method without the mechanical pretreatment and a capacity component 560 of the metal powder of the gas atomization method after the mechanical pretreatment of the present embodiment.
　図５Ｂに示されるように、等価回路モデル５４０の容量成分が本実施例の機械的予備処理により減少し、さらに、低温度（２００℃程）でゼロに近付くので電荷が蓄積されないため、電子ビームの照射によるスモーク現象が発生しない（抑えられる）ものと予測される。 As shown in FIG. 5B, the capacitance component of the equivalent circuit model 540 is reduced by the mechanical pretreatment of the present embodiment, and further closes to zero at a low temperature (about 200 ° C.). It is expected that the smoke phenomenon due to the irradiation will not occur (is suppressed).
　《機械的予備処理後の金属粉末によるスモークテスト》
　図６Ｂは、金属粉末によるスモークテスト方法を説明する図である。 《Smoke test with metal powder after mechanical pretreatment》
FIG. 6B is a diagram illustrating a smoke test method using metal powder.
　金属積層造形装置６３０を用い、手順６４０にしたがって、条件６５０により実施した。スモークテストには、要素技術研究機(電子ビーム加工機)（多田電機株式会社）を使用した。 し た Using the metal additive manufacturing apparatus 630, the procedure 640 was performed under the conditions 650. For the smoke test, an element technology research machine (electron beam processing machine) (Tada Electric Co., Ltd.) was used.
　図６Ａは、金属粉末によるスモークテストの結果６１０を示す図である。図６Ａの結果６１０は、機械的予備処理の無いプラズマアトマイズ法の金属粉末のスモークテスト結果と、本実施例の機械的予備処理後のガスアトマイズ法の金属粉末のスモークテスト結果と、を示している。機械的予備処理の無いプラズマアトマイズ法の金属粉末では、９５０℃の予備加熱によってもスモーク現象が発生している。 FIG. 6A is a diagram showing a result 610 of the smoke test using the metal powder. The result 610 of FIG. 6A shows the smoke test result of the metal powder of the plasma atomization method without the mechanical pretreatment and the smoke test result of the metal powder of the gas atomization method after the mechanical pretreatment of the present example. . In the metal powder of the plasma atomizing method without mechanical pretreatment, the smoke phenomenon occurs even by the preheating at 950 ° C.
　一方、本実施例の機械的予備処理後のガスアトマイズ法の金属粉末では、予備加熱が４５０℃まではスモーク現象が発生するが、６５０℃になるとスモーク現象は発生せず、それ以上の温度６２０で、造形時の溶融温度との関係で広範囲に低い予備加熱の設定が可能となる。図６Ａには示されていないが、５００℃～６００℃の予備加熱においてもスモーク現象が発生しない可能性がある。 On the other hand, in the metal powder of the gas atomization method after the mechanical pretreatment of the present embodiment, the smoke phenomenon occurs until the preheating reaches 450 ° C., but the smoke phenomenon does not occur when the temperature reaches 650 ° C. In addition, it is possible to set a low preheating over a wide range in relation to the melting temperature at the time of molding. Although not shown in FIG. 6A, there is a possibility that the smoke phenomenon does not occur even in preheating at 500 ° C. to 600 ° C.
　［実施例２］
　《機械的予備処理》
　合金粉末の機械的予備処理としては、ボールミルによる機械的予備処理を行った。 [Example 2]
《Mechanical pretreatment》
As mechanical pretreatment of the alloy powder, mechanical pretreatment by a ball mill was performed.
　（ボールミルの装置）
　図８Ｃに、遊星型ボールミル８４０とボールミルの原理８５０とを示す。 (Ball mill equipment)
FIG. 8C shows a planetary ball mill 840 and the principle 850 of the ball mill.
　ボールミルとしては、遊星型ボールミル Classic Line P-7（ドイツ　フリッチュ社）を使用した。条件としては、ディスク回転数（公転）を800RPMとし、ポット回転数（自転）を1600RPM、ボール径はΦ5mmである。処理時間は、反時計周りの公転を15min、時計周りの公転15min、とした。なお、機械的処理中に、金属粉末が１００℃～３００℃に加熱されるのが、容量成分を削減するには望ましい。なお、実際には、ボールミル処理において特に加熱はしておらず、処理直後の容器の温度を測定したところボールの摩擦熱によって１００℃以上になっている。したがって、１００℃～２００℃の加熱しながら機械的処理することによって、より効果的に電気抵抗および容量成分の低下効果が得られると思われる。 The planetary ball mill Classic Line P-7 (Fritsch, Germany) was used as the ball mill. As conditions, the disk rotation speed (revolution) is 800 RPM, the pot rotation speed (rotation) is 1600 RPM, and the ball diameter is Φ5 mm. The processing time was 15 minutes for the counterclockwise revolution and 15 minutes for the clockwise revolution. It is desirable that the metal powder be heated to 100 ° C. to 300 ° C. during the mechanical treatment in order to reduce the capacity component. In practice, the ball mill treatment was not particularly heated, and the temperature of the container immediately after the treatment was 100 ° C. or higher due to the frictional heat of the balls. Therefore, it is considered that the mechanical treatment while heating at 100 ° C. to 200 ° C. can more effectively reduce the electric resistance and the capacitance component.
　《機械的予備処理後の金属粉末表面の物理的特性》
　図８Ａは、本実施例の機械的予備処理後の金属粉末の表面像（ＳＥＭ）８１０と拡大ＳＥＭ像８２０を示す図である。 《Physical properties of metal powder surface after mechanical pretreatment》
FIG. 8A is a diagram showing a surface image (SEM) 810 and an enlarged SEM image 820 of the metal powder after the mechanical pretreatment of the present example.
　拡大ＳＥＭ像８２０において、図２に示したように、デンドランド組織（樹枝状結晶）を含む凝固組織が機械的予備処理における粉末粒子の衝突により平坦化されているのが分かる。したがって、ボールミルによる機械的予備処理を行った金属粉末においても、実施例１と同様に、インピーダンスが小さくなることが予測できる。 (2) In the enlarged SEM image 820, as shown in FIG. 2, it can be seen that the solidified structure including the dendland structure (dendritic crystal) is flattened by the collision of the powder particles in the mechanical pretreatment. Therefore, it can be predicted that the impedance becomes small also in the metal powder subjected to the mechanical pretreatment by the ball mill, as in the first embodiment.
　《機械的予備処理後の金属粉末表面の電気的特性》
　以下の金属粉末表面の電気的特性の測定は、実施例１と同様の装置で行った。 《Electrical properties of metal powder surface after mechanical pretreatment》
The following measurement of the electrical characteristics of the metal powder surface was performed using the same apparatus as in Example 1.
　（インピーダンスの測定結果）
　図８Ｂは、本実施例に係る機械的予備処理後の金属粉末のインピーダンスの変化を示す図である。インピーダンス値が、機械的予備処理の無い金属粉末のインピーダンス（図５Ａの５１０参照）に比較して極端に小さいことが分かる。このことから、その容量成分も小さく、低い予備加熱でゼロに近付くことが予測できる。 (Result of impedance measurement)
FIG. 8B is a diagram illustrating a change in impedance of the metal powder after the mechanical pretreatment according to the present example. It can be seen that the impedance value is extremely small compared to the impedance of the metal powder without mechanical pretreatment (see 510 in FIG. 5A). From this, it can be predicted that the capacity component is small and approaches zero with low preheating.
　（容量成分の算出結果）
　図８Ｂのインピーダンス測定結果から、図５Ｂの等価回路モデル５４０により容量成分を算出したが、容量成分は見られなかった。 (Calculation result of capacitance component)
A capacitance component was calculated from the impedance measurement result in FIG. 8B by the equivalent circuit model 540 in FIG. 5B, but no capacitance component was found.
　したがって、ボールミルによる機械的予備処理によっても、ジェットミルによる機械的予備処理と同様に、予備加熱温度を低下させてもスモーク現象が発生しない金属積層造形用粉末が提供できる。 Therefore, similarly to the mechanical pretreatment using a jet mill, a powder for metal additive manufacturing that does not generate a smoke phenomenon even when the preheating temperature is lowered can be provided by the mechanical pretreatment using a ball mill.
　《他の金属積層造形用粉末》
　次に、ニッケル合金のインコネル718以外に、チタン合金のチタン64（Ti64/Ti-6Al-4V）やチタンアルミニウム(TiAl)を合金粉末として用いてボールミルによる機械的予備処理を行った。 《Powder for other metal additive manufacturing》
Next, in addition to nickel alloy Inconel 718, mechanical pretreatment was performed by a ball mill using titanium alloy titanium 64 (Ti64 / Ti-6Al-4V) or titanium aluminum (TiAl) as an alloy powder.
　（ボールミルの装置）
　図１３に、遊星型ボールミル８４０とボールミルによる処理条件１３１０とを示す。ボールミルとしては、遊星型ボールミル Classic Line P-7（ドイツ　フリッチュ社）を使用した。条件としては、ディスク回転数（公転）を800RPMとし、ポット回転数（自転）を1600RPM、ボール径はΦ5mmである。処理時間は、反時計周りの公転を15min、時計周りの公転15min、の合計30minとした。なお、金属粉末の温度は１００℃～３００℃であった。 (Ball mill equipment)
FIG. 13 shows a planetary ball mill 840 and processing conditions 1310 by the ball mill. As a ball mill, a planetary ball mill Classic Line P-7 (Fritsch, Germany) was used. As conditions, the disk rotation speed (revolution) is 800 RPM, the pot rotation speed (rotation) is 1600 RPM, and the ball diameter is Φ5 mm. The processing time was a total of 30 minutes, that is, 15 minutes for the counterclockwise revolution and 15 minutes for the clockwise revolution. The temperature of the metal powder was 100 ° C. to 300 ° C.
　＜インコネル718/IN718＞
　インコネル718としては、Ａｒｃａｍ社の製品を使用した。使用したインコネル718の特性を、表１に示す。 <Inconel 718 / IN718>
The product of Arcam was used as Inconel 718. The properties of Inconel 718 used are shown in Table 1.
Figure JPOXMLDOC01-appb-T000001
 　
Figure JPOXMLDOC01-appb-T000001
 　
　《機械的予備処理後の金属粉末表面の物理的特性》
　図１４Ａは、本実施例に係る機械的予備処理前後の金属粉末（インコネル718/IN718）の表面像（ＳＥＭ）を示す図である。 《Physical properties of metal powder surface after mechanical pretreatment》
FIG. 14A is a diagram showing a surface image (SEM) of a metal powder (Inconel 718 / IN718) before and after mechanical pretreatment according to the present example.
　図１４Ａにおいて、左上図がボールミル処理前のＳＥＭ画像１４１０であり、右上図がボールミル処理後のＳＥＭ画像１４２０である。左下図がボールミル処理前の拡大ＳＥＭ画像１４１１であり、右下図がボールミル処理後の拡大ＳＥＭ画像１４２１である。右上図および右下図に示したように、デンドランド組織（樹枝状結晶）を含む凝固組織が機械的予備処理における粉末粒子の衝突により平坦化されているのが分かる。したがって、ボールミルによる機械的予備処理を行った金属粉末において、インピーダンスが小さくなることが予測できる。 ＡIn FIG. 14A, the upper left diagram is an SEM image 1410 before ball milling, and the upper right diagram is an SEM image 1420 after ball milling. The lower left diagram is an enlarged SEM image 1411 before ball milling, and the lower right diagram is an enlarged SEM image 1421 after ball milling. As shown in the upper right and lower right figures, it can be seen that the solidified structure including the dendland structure (dendritic crystal) has been flattened by the collision of the powder particles in the mechanical pretreatment. Therefore, it can be predicted that the impedance is reduced in the metal powder that has been subjected to the mechanical pretreatment by the ball mill.
　《機械的予備処理後の金属粉末表面の電気的特性》
　図１４Ｂは、本実施例に係る機械的予備処理後の金属粉末（インコネル718/IN718）の抵抗値の温度変化およびインピーダンスの温度変化を示す図である。なお、金属粉末表面の電気的特性の測定は、実施例１と同様の装置で行った。 《Electrical properties of metal powder surface after mechanical pretreatment》
FIG. 14B is a diagram illustrating a temperature change of the resistance value and a temperature change of the impedance of the metal powder (Inconel 718 / IN718) after the mechanical pretreatment according to the present example. The measurement of the electrical characteristics of the surface of the metal powder was performed using the same apparatus as in Example 1.
　（抵抗値の測定結果）
　図１４Ｂのグラフ１４３０は、図４Ｂ乃至図４Ｅに従い測定された電気抵抗の変化を示す図である。 (Measurement result of resistance value)
A graph 1430 in FIG. 14B is a diagram illustrating a change in electric resistance measured according to FIGS. 4B to 4E.
　図１４Ｂのグラフ１４３０から明らかなように、ボールミル処理後の金属粉末（インコネル718/IN718）の抵抗率は、加熱前の常温（ＲＴ）時から一貫してボールミル処理の無い金属粉末の抵抗率よりも低い（導電性が高い）ので、低温領域でも電子線照射による金属粉末の帯電性が弱まり予備加熱温度を低下することができる。 As is clear from the graph 1430 in FIG. 14B, the resistivity of the metal powder after ball milling (Inconel 718 / IN718) is consistent with the resistivity of metal powder without ball milling from room temperature (RT) before heating. (High conductivity), the chargeability of the metal powder by electron beam irradiation is weakened even in a low temperature region, and the preheating temperature can be lowered.
　（インピーダンスの測定結果）
　図１４Ｂのグラフ群１４４０は、本実施例に係るボールミル処理前後の金属粉末（インコネル718/IN718）のインピーダンスの変化を示す図である。ここで、グラフ群１４４０の右上グラフ１４４１がボールミル処理の無い金属粉末のインピーダンス、グラフ群１４４０の左グラフ１４４２がボールミル処理後の金属粉末のインピーダンス、グラフ群１４４０の右下グラフ１４４３が左グラフ１４４２の原点近傍の拡大グラフである。 (Result of impedance measurement)
A graph group 1440 in FIG. 14B is a diagram illustrating a change in impedance of the metal powder (Inconel 718 / IN718) before and after the ball mill processing according to the present example. Here, the upper right graph 1441 of the graph group 1440 is the impedance of the metal powder without ball milling, the left graph 1442 of the graph group 1440 is the impedance of the metal powder after the ball milling, and the lower right graph 1443 of the graph group 1440 is the left graph 1442. It is an enlarged graph near an origin.
　グラフ群１４４０に示されるように、ボールミル処理後の金属粉末のインピーダンスは、ボールミル処理の無い金属粉末のインピーダンスに比較して極端に小さいことが分かる。このことから、その容量成分も小さく、低い予備加熱でゼロに近付くことが予測できる。 As shown in the graph group 1440, it can be seen that the impedance of the metal powder after ball milling is extremely smaller than the impedance of the metal powder without ball milling. From this, it can be predicted that the capacity component is small and approaches zero with low preheating.
　（容量成分の算出結果）
　図１４Ｃは、本実施例に係るボールミル処理後のインピーダンスの測定結果から、等価回路モデルに基づいて求めた容量成分を示す図である。 (Calculation result of capacitance component)
FIG. 14C is a diagram illustrating a capacitance component obtained based on an equivalent circuit model from the measurement result of the impedance after the ball mill processing according to the present embodiment.
　図１４Ｃのグラフ１４４４は、図１４Ｂのグラフ１４４３をさらに拡大したグラフ、等価回路シミュレーション結果１４５１は、グラフ１４４４のインピーダンスの測定結果からのシミュレーション結果、等価回路モデル１４５２は、等価回路シミュレーション結果１４５１に基づく、ボールミル処理後の金属粉末（インコネル718/IN718）の等価回路モデルである。図１４Ｃの等価回路モデル１４５２から、インピーダンスの測定結果には容量成分が見られないことが分かる。 14C is a graph obtained by further enlarging the graph 1443 of FIG. 14B, an equivalent circuit simulation result 1451 is a simulation result from the impedance measurement result of the graph 1444, and an equivalent circuit model 1452 is based on the equivalent circuit simulation result 1451. 5 is an equivalent circuit model of a metal powder (Inconel 718 / IN718) after ball milling. From the equivalent circuit model 1452 in FIG. 14C, it can be seen that no capacitance component is seen in the impedance measurement result.
　したがって、インピーダンスの測定結果は、ボールミル処理によって、ジェットミルによる機械的予備処理と同様に、予備加熱温度を低下させてもスモーク現象が発生しない金属積層造形用粉末が提供できる。 Therefore, the results of the measurement of the impedance can provide a powder for metal additive manufacturing that does not cause a smoke phenomenon even when the preheating temperature is lowered, similarly to the mechanical pretreatment using a jet mill, by ball milling.
　《機械的予備処理後の金属粉末のＸＰＳ分析結果》
　図１４Ｄは、本実施例に係る機械的予備処理後の金属粉末（インコネル718/IN718）のＸＰＳ分析結果を示す図である。かかるＸＰＳ分析結果は、ボールミル処理による金属粉末（インコネル718/IN718）の材質の変化を検証するためである。 << XPS analysis result of metal powder after mechanical pretreatment >>
FIG. 14D is a diagram showing an XPS analysis result of the metal powder (Inconel 718 / IN718) after the mechanical pretreatment according to the present example. Such XPS analysis results are for verifying the change in the material of the metal powder (Inconel 718 / IN718) due to the ball mill treatment.
　（成分分析結果）
　図１４Ｄの成分分析結果１４６０によれば、ボールミル処理の前後でXPSのピーク位置の違いは見られず、ボールや容器成分の混入は無かった。
　（Ｏ1sスペクトル分析結果）
　図１４ＤのＯ1sスペクトル分析結果１４７０によれば、ボールミル処理後で酸化物イオン（Ｏ2-）が増加している様子が見られた。
　（Ｎ1sスペクトル分析結果）
　図１４ＤのＮ1sスペクトル分析結果１４８０によれば、ボールミル処理後で窒化物が増加している様子が見られた。 (Results of component analysis)
According to the component analysis result 1460 in FIG. 14D, no difference in the XPS peak position was observed before and after the ball mill treatment, and there was no mixing of ball and container components.
(O1s spectrum analysis result)
According to the O1s spectrum analysis result 1470 in FIG. 14D, it was observed that the oxide ions (O 2− ) increased after the ball mill treatment.
(N1s spectrum analysis result)
According to the N1s spectrum analysis result 1480 of FIG. 14D, it was found that nitrides increased after the ball mill treatment.
　＜チタン64/Ti64＞
　チタン64としては、大同特殊鋼株式会社の製品を使用した。使用したチタン64の特性を、表２に示す。 <Titanium 64 / Ti64>
The product of Daido Steel Co., Ltd. was used as titanium 64. Table 2 shows the properties of the titanium 64 used.
Figure JPOXMLDOC01-appb-T000002
 　
Figure JPOXMLDOC01-appb-T000002
 　
　《機械的予備処理後の金属粉末表面の物理的特性》
　図１５Ａは、本実施例に係る機械的予備処理前後の金属粉末（チタン64/Ti64）の表面像（ＳＥＭ）を示す図である。 《Physical properties of metal powder surface after mechanical pretreatment》
FIG. 15A is a diagram showing a surface image (SEM) of the metal powder (titanium 64 / Ti64) before and after the mechanical pretreatment according to the present example.
　図１５Ａにおいて、左上図がボールミル処理前のＳＥＭ画像１５１０であり、右上図がボールミル処理後のＳＥＭ画像１５２０である。左下図がボールミル処理前の拡大ＳＥＭ画像１５１１であり、右下図がボールミル処理後の拡大ＳＥＭ画像１５２１である。右上図および右下図に示したように、デンドランド組織（樹枝状結晶）を含む凝固組織が機械的予備処理における粉末粒子の衝突により平坦化されているのが分かる。したがって、ボールミルによる機械的予備処理を行った金属粉末において、インピーダンスが小さくなることが予測できる。 In FIG. 15A, the upper left figure is the SEM image 1510 before the ball mill processing, and the upper right figure is the SEM image 1520 after the ball mill processing. The lower left diagram is an enlarged SEM image 1511 before ball milling, and the lower right diagram is an enlarged SEM image 1521 after ball milling. As shown in the upper right and lower right figures, it can be seen that the solidified structure including the dendland structure (dendritic crystal) has been flattened by the collision of the powder particles in the mechanical pretreatment. Therefore, it can be predicted that the impedance is reduced in the metal powder that has been subjected to the mechanical pretreatment by the ball mill.
　《機械的予備処理後の金属粉末表面の電気的特性》
　図１５Ｂは、本実施例に係る機械的予備処理後の金属粉末（チタン64/Ti64）の抵抗値の温度変化およびインピーダンスの温度変化を示す図である。なお、金属粉末表面の電気的特性の測定は、実施例１と同様の装置で行った。 《Electrical properties of metal powder surface after mechanical pretreatment》
FIG. 15B is a diagram showing a temperature change of the resistance value and a temperature change of the impedance of the metal powder (titanium 64 / Ti64) after the mechanical pretreatment according to the present example. The measurement of the electrical characteristics of the surface of the metal powder was performed using the same apparatus as in Example 1.
　（抵抗値の測定結果）
　図１５Ｂのグラフ１５３０は、図４Ｂ乃至図４Ｅに従い測定された電気抵抗の変化を示す図である。 (Measurement result of resistance value)
A graph 1530 in FIG. 15B is a diagram illustrating a change in the electric resistance measured according to FIGS. 4B to 4E.
　図１５Ｂのグラフ１５３０から明らかなように、ボールミル処理後の金属粉末（チタン64/Ti64）の抵抗率は、加熱前の常温（ＲＴ）時から一貫してボールミル処理の無い金属粉末の抵抗率と同程度あるいはよりも低い（導電性が高い）ので、低温領域でも電子線照射による金属粉末の帯電性が弱まり予備加熱温度を低下することができる。 As is clear from the graph 1530 in FIG. 15B, the resistivity of the metal powder (titanium 64 / Ti64) after ball milling is consistent with the resistivity of metal powder without ball milling from room temperature (RT) before heating. Since it is the same or lower (higher conductivity), the chargeability of the metal powder by electron beam irradiation is weakened even in a low temperature range, and the preheating temperature can be lowered.
　（インピーダンスの測定結果）
　図１５Ｂのグラフ群１５４０は、本実施例に係るボールミル処理前後の金属粉末（チタン64/Ti64）のインピーダンスの変化を示す図である。ここで、グラフ群１５４０の右上グラフ１５４１がボールミル処理の無い金属粉末のインピーダンス、グラフ群１５４０の左グラフ１５４２がボールミル処理後の金属粉末のインピーダンス、グラフ群１５４０の右下グラフ１５４３が左グラフ１５４２の原点近傍の拡大グラフである。 (Result of impedance measurement)
A graph group 1540 in FIG. 15B is a diagram illustrating a change in impedance of the metal powder (titanium 64 / Ti64) before and after the ball mill treatment according to the present embodiment. Here, the upper right graph 1541 of the graph group 1540 is the impedance of the metal powder without ball milling, the left graph 1542 of the graph group 1540 is the impedance of the metal powder after ball milling, and the lower right graph 1543 of the graph group 1540 is the left graph 1542 of the left graph 1542. It is an enlarged graph near an origin.
　グラフ群１５４０に示されるように、ボールミル処理後の金属粉末のインピーダンスは、ボールミル処理の無い金属粉末のインピーダンスに比較して極端に小さいことが分かる。このことから、その容量成分も小さく、低い予備加熱でゼロに近付くことが予測できる。 As shown in the graph group 1540, it can be seen that the impedance of the metal powder after ball milling is extremely smaller than the impedance of the metal powder without ball milling. From this, it can be predicted that the capacity component is small and approaches zero with low preheating.
　《機械的予備処理後の金属粉末のＸＰＳ分析結果》
　図１５Ｃは、本実施例に係る機械的予備処理後の金属粉末（チタン64/Ti64）のＸＰＳ分析結果を示す図である。かかるＸＰＳ分析結果は、ボールミル処理による金属粉末（チタン64/Ti64）の材質の変化を検証するためである。 << XPS analysis result of metal powder after mechanical pretreatment >>
FIG. 15C is a diagram showing an XPS analysis result of the metal powder (titanium 64 / Ti64) after the mechanical pretreatment according to the present example. The result of the XPS analysis is to verify a change in the material of the metal powder (titanium 64 / Ti64) due to the ball mill treatment.
　（成分分析結果）
　図１５Ｃの成分分析結果１５６０によれば、ボールミル処理の前後でXPSのピーク位置の違いは見られず、ボールや容器成分の混入は無かった。
　（Ｏ1sスペクトル分析結果）
　図１５ＣのＯ1sスペクトル分析結果１５７０によれば、ボールミル処理後で酸化物イオン（Ｏ2-）が増加している様子が見られた。
　（Ｎ1sスペクトル分析結果）
　図１５ＣのＮ1sスペクトル分析結果１５８０によれば、ボールミル処理後で窒化物が増加している様子が見られた。 (Results of component analysis)
According to the component analysis result 1560 in FIG. 15C, no difference in the XPS peak position was observed before and after the ball mill treatment, and there was no mixing of the ball and container components.
(O1s spectrum analysis result)
According to the O1s spectrum analysis result 1570 in FIG. 15C, it was observed that the oxide ions (O 2− ) increased after the ball mill treatment.
(N1s spectrum analysis result)
According to the N1s spectrum analysis result 1580 in FIG. 15C, it was found that the nitride increased after the ball mill treatment.
　＜TiAl＞
　TiAlとしては、大同特殊鋼株式会社の製品を使用した。使用したTiAlの特性を、表３に示す。 <TiAl>
The product of Daido Steel Co., Ltd. was used as TiAl. Table 3 shows the characteristics of the TiAl used.
Figure JPOXMLDOC01-appb-T000003
 　
Figure JPOXMLDOC01-appb-T000003
 　
　《機械的予備処理後の金属粉末表面の物理的特性》
　図１６Ａは、本実施例に係る機械的予備処理前後の金属粉末（チタンアルミニウム合金/TiAl）の表面像（ＳＥＭ）を示す図である。 《Physical properties of metal powder surface after mechanical pretreatment》
FIG. 16A is a diagram showing a surface image (SEM) of a metal powder (titanium aluminum alloy / TiAl) before and after mechanical pretreatment according to the present example.
　図１６Ａにおいて、左上図がボールミル処理前のＳＥＭ画像１６１０であり、右上図がボールミル処理後のＳＥＭ画像１６２０である。左下図がボールミル処理前の拡大ＳＥＭ画像１６１１であり、右下図がボールミル処理後の拡大ＳＥＭ画像１６２１である。右上図および右下図に示したように、デンドランド組織（樹枝状結晶）を含む凝固組織が機械的予備処理における粉末粒子の衝突により平坦化されているのが分かる。したがって、ボールミルによる機械的予備処理を行った金属粉末において、インピーダンスが小さくなることが予測できる。 In FIG. 16A, the upper left diagram is an SEM image 1610 before ball milling, and the upper right diagram is an SEM image 1620 after ball milling. The lower left diagram is an enlarged SEM image 1611 before ball milling, and the lower right diagram is an enlarged SEM image 1621 after ball milling. As shown in the upper right and lower right figures, it can be seen that the solidified structure including the dendland structure (dendritic crystal) has been flattened by the collision of the powder particles in the mechanical pretreatment. Therefore, it can be predicted that the impedance is reduced in the metal powder that has been subjected to the mechanical pretreatment by the ball mill.
　《機械的予備処理後の金属粉末表面の電気的特性》
　図１６Ｂは、本実施例に係る機械的予備処理後の金属粉末（チタンアルミニウム合金/TiAl）の抵抗値の温度変化およびインピーダンスの温度変化を示す図である。なお、金属粉末表面の電気的特性の測定は、実施例１と同様の装置で行った。 《Electrical properties of metal powder surface after mechanical pretreatment》
FIG. 16B is a diagram showing a temperature change of the resistance value and a temperature change of the impedance of the metal powder (titanium aluminum alloy / TiAl) after the mechanical pretreatment according to the present example. The measurement of the electrical characteristics of the surface of the metal powder was performed using the same apparatus as in Example 1.
　（抵抗値の測定結果）
　図１６Ｂのグラフ１６３０は、図４Ｂ乃至図４Ｅに従い測定された電気抵抗の変化を示す図である。 (Measurement result of resistance value)
A graph 1630 in FIG. 16B is a diagram illustrating a change in the electric resistance measured according to FIGS. 4B to 4E.
　図１６Ｂのグラフ１６３０から明らかなように、ボールミル処理後の金属粉末（チタンアルミニウム合金/TiAl）の抵抗率は、加熱前の常温（ＲＴ）時から一貫してボールミル処理の無い金属粉末の抵抗率と同程度あるいはよりも低い（導電性が高い）ので、低温領域でも電子線照射による金属粉末の帯電性が弱まり予備加熱温度を低下することができる。 As is clear from the graph 1630 of FIG. 16B, the resistivity of the metal powder (titanium aluminum alloy / TiAl) after ball milling is consistent with the resistivity of metal powder without ball milling from room temperature (RT) before heating. (Higher conductivity), the chargeability of the metal powder by electron beam irradiation is weakened even in a low temperature range, and the preheating temperature can be lowered.
　（インピーダンスの測定結果）
　図１６Ｂのグラフ群１６４０は、本実施例に係るボールミル処理前後の金属粉末（チタンアルミニウム合金/TiAl）のインピーダンスの変化を示す図である。ここで、グラフ群１６４０の右上グラフ１６４１がボールミル処理の無い金属粉末のインピーダンス、グラフ群１６４０の左グラフ１６４２がボールミル処理後の金属粉末のインピーダンス、グラフ群１６４０の右下グラフ１６４３が左グラフ１６４２の原点近傍の拡大グラフである。 (Result of impedance measurement)
A graph group 1640 in FIG. 16B is a diagram illustrating a change in impedance of the metal powder (titanium aluminum alloy / TiAl) before and after the ball mill treatment according to the present embodiment. Here, the upper right graph 1641 of the graph group 1640 is the impedance of the metal powder without ball milling, the left graph 1642 of the graph group 1640 is the impedance of the metal powder after ball milling, and the lower right graph 1643 of the graph group 1640 is the left graph 1642 It is an enlarged graph near an origin.
　グラフ群１６４０に示されるように、ボールミル処理後の金属粉末のインピーダンスは、ボールミル処理の無い金属粉末のインピーダンスに比較して極端に小さいことが分かる。このことから、その容量成分も小さく、低い予備加熱でゼロに近付くことが予測できる。 As shown in the graph group 1640, it can be seen that the impedance of the metal powder after ball milling is extremely smaller than the impedance of the metal powder without ball milling. From this, it can be predicted that the capacity component is small and approaches zero with low preheating.
　《機械的予備処理後の金属粉末のＸＰＳ分析結果》
　図１６Ｃは、本実施例に係る機械的予備処理後の金属粉末（チタンアルミニウム合金/TiAl）のＸＰＳ分析結果を示す図である。 << XPS analysis result of metal powder after mechanical pretreatment >>
FIG. 16C is a diagram showing an XPS analysis result of the metal powder (titanium aluminum alloy / TiAl) after the mechanical pretreatment according to the present example.
　（成分分析結果）
　図１６Ｃの成分分析結果１６６０によれば、ボールミル処理の前後でXPSのピーク位置の違いは見られず、ボールや容器成分の混入は無かった。
　（Ｏ1sスペクトル分析結果）
　図１６ＣのＯ1sスペクトル分析結果１６７０によれば、ボールミル処理後で酸化物イオン（Ｏ2-）が増加している様子が見られた。
　（Ｎ1sスペクトル分析結果）
　図１６ＣのＮ1sスペクトル分析結果１６８０によれば、ボールミル処理後で窒化物が増加している様子が見られた。 (Results of component analysis)
According to the component analysis result 1660 in FIG. 16C, there was no difference in the XPS peak position before and after the ball mill treatment, and there was no mixing of ball and container components.
(O1s spectrum analysis result)
According to the O1s spectrum analysis result 1670 in FIG. 16C, it was found that the oxide ions (O 2− ) increased after the ball mill treatment.
(N1s spectrum analysis result)
According to the N1s spectrum analysis result 1680 of FIG. 16C, it was found that the nitride increased after the ball mill treatment.
　＜Cu＞
　Cu粉末としては、福田金属箔粉工業株式会社の製品を使用した。使用したCu粉末の特性を、表４に示す。 <Cu>
As Cu powder, a product of Fukuda Metal Foil & Powder Co., Ltd. was used. Table 4 shows the properties of the Cu powder used.
Figure JPOXMLDOC01-appb-T000004
 　
Figure JPOXMLDOC01-appb-T000004
 　
　《機械的予備処理後の金属粉末表面の物理的特性》
　図１７Ａは、本実施例に係る機械的予備処理前後の金属粉末（銅粉末/Cu）の表面像（ＳＥＭ）を示す図である。 《Physical properties of metal powder surface after mechanical pretreatment》
FIG. 17A is a diagram showing a surface image (SEM) of a metal powder (copper powder / Cu) before and after mechanical pretreatment according to the present example.
　図１７Ａにおいて、左図がボールミル処理前のＳＥＭ画像１７１０であり、右図がボールミル処理後のＳＥＭ画像１７２０である。右図に示したように、デンドランド組織（樹枝状結晶）を含む凝固組織が機械的予備処理における粉末粒子の衝突により平坦化されているのが分かる。したがって、ボールミルによる機械的予備処理を行った金属粉末において、インピーダンスが小さくなることが予測できる。 In FIG. 17A, the left figure is the SEM image 1710 before the ball mill processing, and the right figure is the SEM image 1720 after the ball mill processing. As shown in the right figure, it can be seen that the solidified structure including the dendland structure (dendritic crystal) is flattened by the collision of the powder particles in the mechanical pretreatment. Therefore, it can be predicted that the impedance is reduced in the metal powder that has been subjected to the mechanical pretreatment by the ball mill.
　《機械的予備処理後の金属粉末表面の電気的特性》
　図１７Ｂは、本実施例に係る機械的予備処理後の金属粉末（チタンアルミニウム合金/TiAl）の抵抗値の温度変化およびインピーダンスの温度変化を示す図である。なお、金属粉末表面の電気的特性の測定は、実施例１と同様の装置で行った。 《Electrical properties of metal powder surface after mechanical pretreatment》
FIG. 17B is a diagram illustrating a temperature change in the resistance value and a temperature change in the impedance of the metal powder (titanium aluminum alloy / TiAl) after the mechanical pretreatment according to the present example. The measurement of the electrical characteristics of the surface of the metal powder was performed using the same apparatus as in Example 1.
　（抵抗値の測定結果）
　図１７Ｂのグラフ１７３０は、図４Ｂ乃至図４Ｅに従い測定された電気抵抗の変化を示す図である。 (Measurement result of resistance value)
A graph 1730 in FIG. 17B is a diagram illustrating a change in electric resistance measured according to FIGS. 4B to 4E.
　図１７Ｂのグラフ１７３０から明らかなように、ボールミル処理後の金属粉末（銅粉末/Cu）の抵抗率は、加熱前の常温（ＲＴ）時から一貫してボールミル処理の無い金属粉末の抵抗率と同程度あるいはよりも低い（導電性が高い）ので、低温領域でも電子線照射による金属粉末の帯電性が弱まり予備加熱温度を低下することができる。 As is clear from the graph 1730 in FIG. 17B, the resistivity of the metal powder after the ball milling (copper powder / Cu) is consistent with the resistivity of the metal powder without the ball milling from room temperature (RT) before heating. Since it is the same or lower (higher conductivity), the chargeability of the metal powder by electron beam irradiation is weakened even in a low temperature range, and the preheating temperature can be lowered.
　（インピーダンスの測定結果）
　図１７Ｂのグラフ群１７４０は、本実施例に係るボールミル処理前後の金属粉末（銅粉末/Cu）のインピーダンスの変化を示す図である。ここで、グラフ群１７４０の右上グラフ１７４１がボールミル処理の無い金属粉末のインピーダンス、グラフ群１７４０の左グラフ１７４２がボールミル処理後の金属粉末のインピーダンス、グラフ群１７４０の右下グラフ１７４３が左グラフ１７４２の原点近傍の拡大グラフである。 (Result of impedance measurement)
A graph group 1740 in FIG. 17B is a diagram illustrating a change in impedance of the metal powder (copper powder / Cu) before and after the ball mill processing according to the present example. Here, the upper right graph 1741 of the graph group 1740 is the impedance of the metal powder without ball milling, the left graph 1742 of the graph group 1740 is the impedance of the metal powder after ball milling, and the lower right graph 1743 of the graph group 1740 is the left graph 1742 of the left graph 1742. It is an enlarged graph near an origin.
　グラフ群１７４０に示されるように、ボールミル処理後の金属粉末のインピーダンスは、ボールミル処理の無い金属粉末のインピーダンスに比較して極端に小さいことが分かる。このことから、その容量成分も小さく、低い予備加熱でゼロに近付くことが予測できる。 As shown in the graph group 1740, it can be seen that the impedance of the metal powder after ball milling is extremely small compared to the impedance of the metal powder without ball milling. From this, it can be predicted that the capacity component is small and approaches zero with low preheating.
　＜他の金属粉末＞
　その他の金属粉末としては、鉄系(Fe)粉末やタングステン(W)粉末を使用して機械的予備処理を行い、抵抗値の温度変化およびインピーダンスの温度変化の測定を行った。いずれも、抵抗値の温度変化およびインピーダンスの温度変化において、同様の改善傾向が見られた。使用したタングシテン(W)粉末の特性を、表５に示す。 <Other metal powder>
As other metal powders, iron (Fe) powder or tungsten (W) powder was used for mechanical pretreatment, and the temperature change of the resistance value and the temperature change of the impedance were measured. In each case, similar improvements were observed in the temperature change of the resistance value and the temperature change of the impedance. Table 5 shows the properties of the used tongue sten (W) powder.
Figure JPOXMLDOC01-appb-T000005
Figure JPOXMLDOC01-appb-T000005
　《処理時間を変えた機械的予備処理》
　次に、ニッケル合金のインコネル718を用いてボールミルによる処理時間を変えて機械的予備処理を行った。インコネル718としては、Ａｒｃａｍ社の製品を使用した。製品の特性は、表１に示した。 《Mechanical preliminary processing with different processing time》
Next, mechanical pretreatment was performed using nickel alloy Inconel 718 while changing the treatment time by a ball mill. The product of Arcam was used as Inconel 718. The properties of the product are shown in Table 1.
　（異なる時間の動作条件）
　図１８は、本実施例に係る機械的予備処理を行ったボールミル８４０およびその異なる時間の動作条件１８１０を示す図である。なお、処理時間以外の条件は、実施例３と同様である。 (Operating conditions at different times)
FIG. 18 is a diagram illustrating a ball mill 840 that has undergone mechanical pretreatment according to the present embodiment and operating conditions 1810 at different times. The conditions other than the processing time are the same as in the third embodiment.
　《機械的予備処理後の金属粉末表面の物理的特性》
　図１９は、本実施例に係る異なる時間の機械的予備処理後の金属粉末（インコネル718/IN718）の表面像（ＳＥＭ）を示す図である。図１９には、１０分処理後のＳＥＭ画像１９１０と、３０分処理後のＳＥＭ画像１９２０と、６０分処理後のＳＥＭ画像１９３０と、が示されている。 《Physical properties of metal powder surface after mechanical pretreatment》
FIG. 19 is a diagram showing a surface image (SEM) of the metal powder (Inconel 718 / IN718) after the mechanical pretreatment at different times according to the present example. FIG. 19 shows an SEM image 1910 after the processing for 10 minutes, an SEM image 1920 after the processing for 30 minutes, and an SEM image 1930 after the processing for 60 minutes.
　図１９に示したように、ＳＥＭ画像１９１０および１９２０においては、デンドランド組織（樹枝状結晶）を含む凝固組織が機械的予備処理における粉末粒子の衝突により平坦化されているのが分かる。したがって、ボールミルによる機械的予備処理を行った金属粉末において、インピーダンスが小さくなることが予測できる。しかしながら、ＳＥＭ画像１９３０においては、金属粉末（インコネル718/IN718）が崩れて凝集していることが分かる。 As shown in FIG. 19, in the SEM images 1910 and 1920, it can be seen that the solidified structure including the dendland structure (dendritic crystal) is flattened by the collision of the powder particles in the mechanical pretreatment. Therefore, it can be predicted that the impedance is reduced in the metal powder that has been subjected to the mechanical pretreatment by the ball mill. However, it can be seen from the SEM image 1930 that the metal powder (Inconel 718 / IN718) has collapsed and aggregated.
　図２０は、本実施例に係る適切な時間を超えた機械的予備処理後の金属粉末（インコネル718/IN718）の状態２０１０を示す図である。すなわち、ボールミル８４０による６０分処理後の金属粉末（インコネル718/IN718）の状態２０１０を示す図であり、800rpmで処理時間を６０分まで長くボールミル処理をしてしまうと粉砕ボールおよびミル容器と粉末が合金化してしまう様子が見られた。したがって、本条件によるボールミル処理は６０分を超えないことが好ましく、３０分当たりがより好ましいと思われる。 FIG. 20 is a diagram showing a state 2010 of the metal powder (Inconel 718 / IN718) after the mechanical pre-treatment exceeding the appropriate time according to the present embodiment. That is, it is a diagram showing a state 2010 of the metal powder (Inconel 718 / IN718) after a 60-minute treatment by a ball mill 840. If the ball mill treatment is performed at 800 rpm for a long treatment time up to 60 minutes, the pulverized ball and the mill container and powder Was seen to be alloyed. Therefore, it is preferable that the ball mill treatment under these conditions does not exceed 60 minutes, and it is more preferable that the ball mill treatment is performed per 30 minutes.
　《機械的予備処理後の金属粉末表面の電気的特性》
　（抵抗値の測定結果）
　図２１は、本実施例に係る異なる時間の機械的予備処理後の金属粉末（インコネル718/IN718）の抵抗値の温度変化を示す図である。図２１は、異なる時間の機械的予備処理後に、図４Ｂ乃至図４Ｅに従い測定された電気抵抗の変化を示す図である。 《Electrical properties of metal powder surface after mechanical pretreatment》
(Measurement result of resistance value)
FIG. 21 is a diagram illustrating a temperature change of the resistance value of the metal powder (Inconel 718 / IN718) after the mechanical pretreatment for different times according to the present example. FIG. 21 shows the change in electrical resistance measured according to FIGS. 4B to 4E after mechanical pretreatment at different times.
　図２１から明らかなように、ボールミル処理後の金属粉末（インコネル718/IN718）の抵抗率は、１０分および３０分のいずれのボールミル処理後も、加熱前の常温（ＲＴ）時から一貫してボールミル処理の無い金属粉末の抵抗率と同程度あるいはよりも低い（導電性が高い）ので、低温領域でも電子線照射による金属粉末の帯電性が弱まり予備加熱温度を低下することができると思われる。しかし、６０分の処理後には、予備加熱による抵抗率低下の効果が小さくなっている。 As is clear from FIG. 21, the resistivity of the metal powder (Inconel 718 / IN718) after the ball mill treatment was consistent from room temperature (RT) before heating even after the ball mill treatment for 10 minutes and 30 minutes. Since the resistivity of the metal powder without ball milling is about the same as or lower than that of the metal powder (high conductivity), it is considered that the chargeability of the metal powder by electron beam irradiation is weakened even in a low temperature region and the preheating temperature can be lowered. . However, after the treatment for 60 minutes, the effect of lowering the resistivity by the preheating is small.
　（インピーダンスの測定結果）
　図２２は、本実施例に係る異なる時間の機械的予備処理後の金属粉末（インコネル718/IN718）のインピーダンスの温度変化を示す図である。図２２には、１０分処理後のインピーダンス測定結果２２１０と、３０分処理後のインピーダンス測定結果２２２０と、６０分処理後のインピーダンス測定結果２２３０と、が示されている。 (Result of impedance measurement)
FIG. 22 is a diagram illustrating a temperature change of the impedance of the metal powder (Inconel 718 / IN718) after the mechanical pretreatment for different times according to the present example. FIG. 22 shows an impedance measurement result 2210 after the 10-minute processing, an impedance measurement result 2220 after the 30-minute processing, and an impedance measurement result 2230 after the 60-minute processing.
　そして、インピーダンス測定結果２２１０の右上グラフ２２１１がボールミル処理の無い金属粉末のインピーダンス、左グラフ２２１２がボールミル処理後の金属粉末のインピーダンス、右下グラフ２２１３が左グラフ２２１２の原点近傍の拡大グラフである。また、インピーダンス測定結果２２２０の右上グラフ２２２１がボールミル処理の無い金属粉末のインピーダンス、左グラフ２２２２がボールミル処理後の金属粉末のインピーダンス、右下グラフ２２２３が左グラフ２２２２の原点近傍の拡大グラフである。また、インピーダンス測定結果２２３０の右上グラフ２２３１がボールミル処理の無い金属粉末のインピーダンス、左グラフ２２３２がボールミル処理後の金属粉末のインピーダンス、右下グラフ２２３３が左グラフ２２３２の原点近傍の拡大グラフである。 The upper right graph 2211 of the impedance measurement result 2210 is the impedance of the metal powder without ball milling, the left graph 2212 is the impedance of the metal powder after ball milling, and the lower right graph 2213 is an enlarged graph near the origin of the left graph 2212. The upper right graph 2221 of the impedance measurement result 2220 is the impedance of the metal powder without ball milling, the left graph 2222 is the impedance of the metal powder after ball milling, and the lower right graph 2223 is an enlarged graph near the origin of the left graph 2222. The upper right graph 2231 of the impedance measurement result 2230 is the impedance of the metal powder without ball milling, the left graph 2232 is the impedance of the metal powder after ball milling, and the lower right graph 2233 is an enlarged graph near the origin of the left graph 2232.
　いずれのインピーダンス測定結果２２１０～２２３０に示されるように、ボールミル処理後の金属粉末のインピーダンスは、ボールミル処理の無い金属粉末のインピーダンスに比較して極端に小さいことが分かる。このことから、その容量成分も小さく、低い予備加熱でゼロに近付くことが予測できる。 As shown in any of the impedance measurement results 2210 to 2230, it can be seen that the impedance of the metal powder after ball milling is extremely smaller than the impedance of metal powder without ball milling. From this, it can be predicted that the capacity component is small and approaches zero with low preheating.
　《ボールミルの処理時間の考察》
　本実施例における、表面のＳＥＭ画像、ボールミル処理後の粉末の状態、抵抗値の測定結果、および、インピーダンスの測定結果から複合的に判断すると、本条件によるボールミル処理は１０分以上で６０分を超えないことが好ましく、３０分当たりがより好ましいと思われる。なお、ボール寸法、回転数、温度などの動作条件により好ましい時間帯が変わるものと考えられる。 《Consideration of ball mill processing time》
In the present embodiment, when judging from the SEM image of the surface, the state of the powder after the ball mill treatment, the measurement result of the resistance value, and the measurement result of the impedance, the ball mill treatment under this condition takes 60 minutes in 10 minutes or more. It is preferred not to exceed, and more preferably around 30 minutes. It is considered that the preferable time zone changes depending on operating conditions such as the ball size, the number of rotations, and the temperature.
　《機械的予備処理後の金属粉末によるスモークテスト》
　（スモークテスト結果）
　図２３は、本実施例に係る機械的予備処理後の金属粉末によるスモークテストの結果２３１０を示す図である。 《Smoke test with metal powder after mechanical pretreatment》
(Smoke test result)
FIG. 23 is a diagram illustrating a result 2310 of the smoke test using the metal powder after the mechanical pretreatment according to the present embodiment.
　図２３に示すように、本実施例に係るボールミル処理による機械的予備処理前には、７００℃以上の予備加熱がなければスモーク現象を抑制でできなかったが、本実施例に係るボールミル処理による機械的予備処理後には、室温（ＲＴ）においてもスモーク現象の発生はなかった。したがって、溶融ビームの条件によっては、室温で予備加熱無しであってもスモークが発生しないという結果が得られた。しかしながら、溶融条件で一番厳しいと思われる条件を想定すると、現状の溶融条件では６００～５００℃まで予備加熱を実施することが望ましい。以下、この結果を得たスモークテストについて説明する。 As shown in FIG. 23, before the mechanical pretreatment by the ball milling according to the present embodiment, the smoke phenomenon could not be suppressed without the preheating at 700 ° C. or higher. After the mechanical pretreatment, no smoke phenomenon occurred even at room temperature (RT). Therefore, depending on the conditions of the molten beam, the result was obtained that no smoke was generated even at room temperature without preheating. However, assuming the most severe melting conditions, it is desirable to perform preheating to 600 to 500 ° C. under the current melting conditions. Hereinafter, the smoke test that has obtained this result will be described.
　（スモークテスト方法および条件）
　図２４は、本実施例に係る機械的予備処理後の金属粉末によるスモークテスト方法を説明する図である。 (Smoke test method and conditions)
FIG. 24 is a diagram illustrating a smoke test method using metal powder after mechanical pretreatment according to the present embodiment.
　図２４のスモークテスト・システム２４１０は、スモークテスト対象の積層造形用金属粉末へのビーム照射を制御するビーム照射制御部と、ビーム照射された積層造形用金属粉末の状態を観察する金属粉末観察部と、を備える。ビーム照射制御部は、造形データを生成する造形装置（ＰＣ）と、造形装置からのビームオン指令に対応してビームの出力を制御するビーム出力制御基板と、ビーム出力制御基板からのビーム出力信号によりビームを出力するビーム出力部と、を含む。また、金属粉末観察部は、スモークテスト中の積層造形用金属粉末を撮像する高速度カメラと、ビーム出力制御基板からの制御信号に同期して高速度カメラによる撮像タイミングを制御するオシロスコープと、高速度カメラを制御して撮像画像を取得して記憶するカメラ制御・記憶装置（ＰＣ）と、を含む。なお、図２４のスモークテスト・システムは一例であって、これに限定されるものではない。 The smoke test system 2410 in FIG. 24 includes a beam irradiation control unit that controls the beam irradiation on the additive manufacturing metal powder to be subjected to the smoke test, and a metal powder observation unit that observes the state of the beam-irradiated additive manufacturing metal powder. And. The beam irradiation control unit includes a modeling device (PC) that generates modeling data, a beam output control board that controls a beam output in response to a beam-on command from the modeling device, and a beam output signal from the beam output control board. A beam output unit that outputs a beam. Further, the metal powder observation unit includes a high-speed camera for imaging the metal powder for additive manufacturing during the smoke test, an oscilloscope for controlling the imaging timing of the high-speed camera in synchronization with a control signal from the beam output control board, and a high-speed camera. A camera control and storage device (PC) for controlling the speed camera to acquire and store the captured image. Note that the smoke test system in FIG. 24 is an example, and the present invention is not limited to this.
　図２５は、本実施例に係る機械的予備処理後の金属粉末によるスモークテスト条件を示す図である。すなわち、図２４のスモークテスト・システム２４１０における動作条件を含むスモークテスト条件である。 FIG. 25 is a diagram showing smoke test conditions using metal powder after mechanical pretreatment according to the present example. That is, the smoke test condition includes the operation condition in the smoke test system 2410 of FIG.
　図２５には、高速度カメラのカメラ条件２５１０と、スモークテスト対象の積層造形用金属粉末を配置する配置部の構造２５２０と、ビーム出力制御基板からのビームオン信号２５３０と、が示されている。 FIG. 25 shows a camera condition 2510 of the high-speed camera, a structure 2520 of an arrangement portion for arranging the metal powder for additive manufacturing to be subjected to the smoke test, and a beam-on signal 2530 from the beam output control board.
　［実施例３］
　《表面被覆処理》
　次に、金属粉末の表面をめっきにより金属被覆する処理について説明する。めっき装置によるコーティングには、上村工業株式会社製の「フロースループレーターＲＰ－１」を使用した。なお、株式会社奈良機械製作所製の「ハイブリダイゼーションシステムＮＨＳ－Ｏ型」を使用した成膜処理法によるコーティングによっても、めっき処理と同等の効果があった。 [Example 3]
《Surface coating treatment》
Next, a process of metal-coating the surface of the metal powder by plating will be described. For coating with a plating apparatus, “Flow Slooplator RP-1” manufactured by Uemura Kogyo Co., Ltd. was used. It should be noted that the same effect as the plating treatment was obtained by coating using a film forming method using "Hybridization System NHS-O" manufactured by Nara Machinery Co., Ltd.
　《機械的予備処理後の金属粉末表面の物理的特性》
　図９Ａは、本実施例に係る表面被覆処理後の金属粉末の表面像（ＳＥＭ）および被覆膜厚９１０～９３０を示す図である。 《Physical properties of metal powder surface after mechanical pretreatment》
FIG. 9A is a diagram showing a surface image (SEM) and a coating film thickness of 910 to 930 of the metal powder after the surface coating treatment according to the present example.
　ＳＥＭ像９１０～９３０において、デンドランド組織（樹枝状結晶）を含む凝固組織が金属被覆処理により緩和されているのが分かる。したがって、表面被覆処理を行った金属粉末においても、実施例１および２と同様に、インピーダンスが小さくなることが予測できる。 From the SEM images 910 to 930, it can be seen that the solidified structure including the dendland structure (dendritic crystal) has been alleviated by the metal coating treatment. Therefore, it can be predicted that the impedance becomes small also in the metal powder subjected to the surface coating treatment, as in Examples 1 and 2.
　図９Ｂは、本実施例に係る表面被覆処理後の金属粉末の表面分析結果（ＸＰＳ）９４０を示す図である。図９Ｂによれば、表面は酸化被膜でなく水酸化基物であり、酸化層は見られなかった。 FIG. 9B is a diagram showing a surface analysis result (XPS) 940 of the metal powder after the surface coating treatment according to this example. According to FIG. 9B, the surface was not an oxide film but a hydroxyl group, and no oxide layer was observed.
　《機械的予備処理後の金属粉末表面の電気的特性》
　以下の金属粉末表面の電気的特性の測定は、実施例１および２と同様の装置で行った。 《Electrical properties of metal powder surface after mechanical pretreatment》
The following measurement of the electrical characteristics of the metal powder surface was performed using the same apparatus as in Examples 1 and 2.
　（電気抵抗の測定結果）
　図９Ｃは、本実施例に係る表面被覆処理後の金属粉末の抵抗値の温度変化９５０を示す図である。 (Measurement result of electric resistance)
FIG. 9C is a diagram illustrating a temperature change 950 of the resistance value of the metal powder after the surface coating treatment according to the present embodiment.
　図９Ｃから明らかなように、金属被覆処理後の金属粉末は、加熱前の常温（ＲＴ）時から一貫して金属被覆処理の無い金属粉末よりも、電気抵抗が低い（導電性が高い）ので、低温領域でも電子線照射による金属粉末の帯電性が弱まり、より予備加熱温度を低下することができる。 As is clear from FIG. 9C, the metal powder after the metal coating treatment has lower electric resistance (higher conductivity) than the metal powder without the metal coating treatment from room temperature (RT) before heating. In addition, even in a low temperature region, the chargeability of the metal powder by electron beam irradiation is weakened, and the preheating temperature can be further reduced.
　（インピーダンスの測定結果）
　図９Ｄは、本実施例に係る表面被覆処理後の金属粉末のインピーダンスの変化９７０を示す図である。図９Ｄから明らかなように、本実施例の金属被覆処理後の金属粉末は、常温（ＲＴ）からの全ての温度で１桁（XΩ)以下となる。 (Result of impedance measurement)
FIG. 9D is a diagram illustrating a change 970 of the impedance of the metal powder after the surface coating treatment according to the present embodiment. As is clear from FIG. 9D, the metal powder after the metal coating treatment of the present example is lower than one digit (XΩ) at all temperatures from room temperature (RT).
　《金属被覆処理後の金属粉末によるスモークテスト》
　スモークテストは、図６Ａに示した装置と手順で実施した。 《Smoke test with metal powder after metal coating treatment》
The smoke test was performed using the apparatus and procedure shown in FIG. 6A.
　図９Ｅは、金属被覆処理後の金属粉末によるスモークテストの結果９８０を示す図である。図９Ｅの結果９８０は、本実施例の金属被覆処理後のプラズマアトマイズ法の金属粉末のスモークテスト結果と、金属被覆処理後のガスアトマイズ法の金属粉末のスモークテスト結果と、を示している。 FIG. 9E is a diagram showing a result 980 of the smoke test using the metal powder after the metal coating treatment. The result 980 in FIG. 9E shows the smoke test result of the metal atomized by the plasma atomizing method after the metal coating treatment of the present example and the smoke test result of the gas atomized by the gas atomizing method after the metal coating treatment.
　本実施例の金属被覆処理後のプラズマアトマイズ法の金属粉末では、３５０℃まではスモーク現象が発生するが、４５０℃からは発生しなかった。また、本実施例の金属被覆処理後のガスアトマイズ法の金属粉末では、常温（ＲＴ）からスモーク現象は発生しなかった（図９Ｅの９８１参照）。 プ ラ ズ マ In the metal powder of the plasma atomizing method after the metal coating treatment in this example, the smoke phenomenon occurred up to 350 ° C., but did not occur from 450 ° C. Further, in the metal powder of the gas atomization method after the metal coating treatment of the present example, no smoke phenomenon occurred from room temperature (RT) (see 981 in FIG. 9E).
　《本実施例の効果》
　本実施例によれば、容量成分で金属粉末を評価することによって、予備加熱温度を低下させてもスモーク現象が発生しない金属積層造形用粉末であるか否かが判定される。そして、容量成分を低下させるための様々な金属粉末の表面処理を施すことによって、予備加熱温度を低下させてもスモーク現象が発生しない金属積層造形用粉末を提供できる。 << Effect of this embodiment >>
According to this embodiment, by evaluating the metal powder by the capacity component, it is determined whether or not the powder is a metal additive manufacturing powder that does not cause a smoke phenomenon even when the preheating temperature is lowered. Then, by performing surface treatment of various metal powders to reduce the capacity component, it is possible to provide a powder for metal additive manufacturing that does not cause a smoke phenomenon even when the preheating temperature is reduced.
　例えば、ジェットミルによる機械的予備処理を行うことによって、電気抵抗およびインピーダンスを低下させ、容量成分がゼロに近付く温度を下げることにより、予備加熱温度を低下させてもスモーク現象が発生しない金属積層造形用粉末を提供する。また、ボールミルによる機械的予備処理を行うことによって、電気抵抗およびインピーダンスを低下させ、容量成分がゼロに近付く温度を下げることにより、予備加熱温度を低下させてもスモーク現象が発生しない金属積層造形用粉末を提供する。なお、本実施例では、ジェットミルとボールミルとによる機械的予備処理を示したが、金属粉末を衝突させてインピーダンス、特にその容量成分を低減させることができる機械的処理であれば、ジェットミルとボールミルとに限らず同様の効果を奏すものである。 For example, by performing a mechanical pretreatment using a jet mill, the electrical resistance and impedance are reduced, and by lowering the temperature at which the capacitance component approaches zero, the metal additive manufacturing that does not cause a smoke phenomenon even when the preheating temperature is reduced. Provide powder for use. In addition, by performing a mechanical pretreatment using a ball mill, the electrical resistance and impedance are reduced, and the temperature at which the capacitance component approaches zero is reduced, so that the smoke phenomenon does not occur even if the preheating temperature is reduced. Provide powder. In the present embodiment, the mechanical pretreatment by the jet mill and the ball mill is described. The same effect can be obtained without being limited to the ball mill.
　さらに、金属めっきなどの表面被覆処理を行うことによって、電気抵抗およびインピーダンスを低下させ、容量成分がゼロに近付く温度を下げることにより、予備加熱温度を低下させてもスモーク現象が発生しない金属積層造形用粉末を提供する。 In addition, by performing surface coating treatment such as metal plating, the electrical resistance and impedance are reduced, and the temperature at which the capacitance component approaches zero is reduced, so that the metal additive manufacturing that does not cause a smoke phenomenon even if the preheating temperature is reduced. Provide powder for use.
　［金属積層造形用粉末の他の実施形態］
　上記実施例においては、合金粉末として、ニッケル系合金のインコネル718(登録商標：Inconel 718／UNS Number N07718)、チタン系合金のチタン64やTiAlなど、を使用したが、合金粉末はこれに限定されない。 [Another embodiment of powder for metal additive manufacturing]
In the above embodiment, as the alloy powder, nickel-based alloy Inconel 718 (registered trademark: Inconel 718 / UNS Number N07718), titanium-based alloy such as titanium 64 or TiAl was used, but the alloy powder is not limited to this. .
　図１０に、本発明を適用可能な他の合金粉末の例１０００を示す。これら他の合金粉末は、他のニッケル系合金や、ニッケルを所定比率含有する他の金属系合金、例えば、コバルト系合金や鉄系合金、銅合金、タングステン合金などを含む。 FIG. 10 shows an example 1000 of another alloy powder to which the present invention can be applied. These other alloy powders include other nickel-based alloys and other metal-based alloys containing a predetermined ratio of nickel, such as cobalt-based alloys, iron-based alloys, copper alloys, and tungsten alloys.
　［金属積層造形装置の実施形態］
　本発明の実施形態に係る金属積層造形装置について説明する。本実施形態に係る金属積層造形装置は、本実施形態の機械的予備処理を行う機能を有する。 [Embodiment of metal additive manufacturing apparatus]
The metal additive manufacturing apparatus according to the embodiment of the present invention will be described. The metal additive manufacturing apparatus according to the present embodiment has a function of performing the mechanical pretreatment of the present embodiment.
　《金属積層造形装置の構成》
　図１１は、本実施形態に係る金属積層造形装置１１００の構成を示すブロック図である。 《Configuration of metal additive manufacturing equipment》
FIG. 11 is a block diagram illustrating a configuration of the metal additive manufacturing apparatus 1100 according to the present embodiment.
　金属積層造形装置１１００は、情報処理装置１１１０と、積層造形装置１１２０と、を備える。 積 層 The metal additive manufacturing apparatus 1100 includes an information processing apparatus 1110 and an additive manufacturing apparatus 1120.
　情報処理装置１１１０は、通信制御部１１１１と、入出力インタフェース１１１２と、表示部１１１３と、操作部１１１４と、オプションとして記憶媒体と、を備える。また、情報処理装置１１１０は、データベース１１１５と、インピーダンス取得部１１１６と、容量成分算出部１１１７と、金属粉末評価部１１１８と、予備加熱設定部１１１９と、を備える。 The information processing apparatus 1110 includes a communication control unit 1111, an input / output interface 1112, a display unit 1113, an operation unit 1114, and a storage medium as an option. Further, the information processing device 1110 includes a database 1115, an impedance acquisition unit 1116, a capacitance component calculation unit 1117, a metal powder evaluation unit 1118, and a preheating setting unit 1119.
　通信制御部１１１１は、積層造形装置１１２０の造形制御部１１２１および外部のインピーダンス測定装置１１３０との通信を制御する。入出力インタフェース１１１２は、表示部１１１３、操作部１１１４、記憶媒体、との入出力をインタフェースする。なお、表示部１１１３と操作部１１１４は、タッチパネルとして合体していてもよい。データベース１１１５は、情報処理装置１１１１が本実施形態の処理をするためのデータを保持する。例えば、インピーダンスから容量成分を算出するためのアルゴリズムや、容量成分から金属粉末を評価するためのアルゴリズムを格納する。また、インピーダンスから容量成分を算出するためのテーブルや、容量成分から金属粉末を評価するためのテーブルを記憶する。 The communication control unit 1111 controls communication with the modeling control unit 1121 of the additive manufacturing device 1120 and the external impedance measuring device 1130. The input / output interface 1112 interfaces input and output with the display unit 1113, the operation unit 1114, and the storage medium. Note that the display unit 1113 and the operation unit 1114 may be combined as a touch panel. The database 1115 holds data for the information processing device 1111 to perform the processing of the present embodiment. For example, an algorithm for calculating the capacitance component from the impedance and an algorithm for evaluating the metal powder from the capacitance component are stored. Also, a table for calculating a capacitance component from the impedance and a table for evaluating metal powder from the capacitance component are stored.
　インピーダンス取得部１１１６は、インピーダンス測定装置１１３０から評価対象の金属粉末のインピーダンス情報を取得する。なお、評価対象の金属粉末のインピーダンス情報は、記憶媒体から取得してもよい。容量成分算出部１１１７は、インピーダンス情報からデータベース１１１５に格納されたアルゴリズムに従って容量成分を算出する。金属粉末評価部１１１８は、算出された容量成分に基づいてデータベース１１１５に格納されたアルゴリズムに従って評価対象の金属粉末を評価する。予備加熱設定部１１１９は、金属粉末評価部１１１８の結果やオペレータの操作などに基づいて、積層造形装置１１２０における予備加熱温度を設定する。 The impedance acquiring unit 1116 acquires the impedance information of the metal powder to be evaluated from the impedance measuring device 1130. The impedance information of the metal powder to be evaluated may be obtained from a storage medium. The capacitance component calculation unit 1117 calculates a capacitance component from the impedance information according to an algorithm stored in the database 1115. The metal powder evaluation unit 1118 evaluates the metal powder to be evaluated according to the algorithm stored in the database 1115 based on the calculated capacity component. The preheating setting unit 1119 sets a preheating temperature in the additive manufacturing apparatus 1120 based on a result of the metal powder evaluation unit 1118, an operation of an operator, and the like.
　（情報処理装置の表示例）
　図１２Ａは、本実施形態に係る金属積層造形装置１１００の情報処理装置１１１０の表示例を示す図である。図１２Ａの表示例は、図１１の表示部１１１３および操作部１１１４により実現される。 (Display example of information processing device)
FIG. 12A is a diagram illustrating a display example of the information processing apparatus 1110 of the metal additive manufacturing apparatus 1100 according to the present embodiment. The display example in FIG. 12A is realized by the display unit 1113 and the operation unit 1114 in FIG.
　表示画面１２１０には、金属粉末の製造会社や製品名などが出力される。そして、表示画面１２１０には、評価結果１２１１が出力される。その評価結果１２１１となった特性が出力され、例えば、容量成分がゼロとなる温度１２１２が出力される。さらに、機械的予備処理や表面被覆処理などの要否１２１３が出力される。なお、出力情報は図１２に限定されない。 The display screen 1210 outputs a metal powder manufacturing company, a product name, and the like. Then, the evaluation result 1211 is output to the display screen 1210. The characteristic that is the evaluation result 1211 is output, for example, a temperature 1212 at which the capacitance component becomes zero is output. Further, the necessity 1213 of the mechanical pretreatment or the surface coating treatment is output. Note that the output information is not limited to FIG.
　《情報処理装置の処理手順》
　図１２Ｂは、本実施形態に係る金属積層造形装置１１００の情報処理装置１１１０の処理手順を示すフローチャートである。このフローチャートは、情報処理装置１１１０を制御するＣＰＵによりＲＡＭを使用して実行され、図１１の情報処理装置１１１０の機能構成部を実現する。 << Processing procedure of information processing device >>
FIG. 12B is a flowchart illustrating a processing procedure of the information processing apparatus 1110 of the metal additive manufacturing apparatus 1100 according to the present embodiment. This flowchart is executed by the CPU that controls the information processing device 1110 using the RAM, and implements the functional components of the information processing device 1110 in FIG.
　情報処理装置１１１０は、ステップＳ１２１１において、評価対象の金属粉末のインピーダンス情報を取得する。情報処理装置１１１０は、ステップＳ１２１３において、インピーダンスから評価対象の金属粉末の容量成分を算出する。そして、情報処理装置１１１０は、ステップＳ１２１５において、算出された容量成分がゼロに近付く温度が所定温度αより低いか否かを判定する。容量成分がゼロに近付く温度が所定温度αより低い場合、情報処理装置１１１０は、ステップＳ１２１７において、評価対象の金属粉末の評価が良好であることを通知する。一方、容量成分がゼロに近付く温度が所定温度αより高い場合、情報処理装置１１１０は、ステップＳ１２１９において、評価対象の金属粉末の評価が良好でないことを通知する。 In step S1211, the information processing apparatus 1110 acquires impedance information of the metal powder to be evaluated. In step S1213, the information processing device 1110 calculates a capacitance component of the metal powder to be evaluated from the impedance. Then, in step S1215, the information processing device 1110 determines whether or not the temperature at which the calculated capacitance component approaches zero is lower than the predetermined temperature α. When the temperature at which the capacitance component approaches zero is lower than the predetermined temperature α, in step S1217, the information processing device 1110 notifies that the evaluation of the metal powder to be evaluated is good. On the other hand, when the temperature at which the capacitance component approaches zero is higher than the predetermined temperature α, in step S1219, the information processing device 1110 notifies that the evaluation of the metal powder to be evaluated is not good.
　本実施形態の金属積層造形装置とその情報処理装置によれば、使用する金属粉末を予備加熱が低くて済む金属粉末か否かを評価することで、効率的な金属積層造形を実現することができる。すなわち、予備加熱温度を低下させることで全体の積層造形時間が短縮され、生産性が向上すると共に、予備加熱温度が低下することで積層造形後の不要粉末除去が容易となる。 According to the metal additive manufacturing apparatus and the information processing apparatus thereof of the present embodiment, it is possible to realize an efficient metal additive manufacturing by evaluating whether or not a metal powder to be used is a metal powder requiring low preheating. it can. That is, by lowering the preheating temperature, the overall lamination molding time is shortened, productivity is improved, and by lowering the preheating temperature, unnecessary powder removal after lamination molding is facilitated.
　［他の実施形態］
　なお、実施形態を参照して本願発明を説明したが、本願発明は上記実施形態に限定されるものではない。本願発明の構成や詳細には、本願発明のスコープ内で当業者が理解し得る様々な変更をすることができる。また、それぞれの実施形態に含まれる別々の特徴を如何様に組み合わせたシステムまたは装置も、本発明の範疇に含まれる。 [Other embodiments]
Although the present invention has been described with reference to the exemplary embodiments, the present invention is not limited to the above exemplary embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention. In addition, a system or an apparatus in which different features included in each embodiment are combined in any way is also included in the scope of the present invention.
　また、本発明は、複数の機器から構成されるシステムに適用されてもよいし、単体の装置に適用されてもよい。さらに、本発明は、実施形態の機能を実現する情報処理プログラムが、システムあるいは装置に直接あるいは遠隔から供給される場合にも適用可能である。したがって、本発明の機能をコンピュータで実現するために、コンピュータにインストールされるプログラム、あるいはそのプログラムを格納した媒体、そのプログラムをダウンロードさせるＷＷＷ(World Wide Web)サーバも、本発明の範疇に含まれる。特に、少なくとも、上述した実施形態に含まれる処理ステップをコンピュータに実行させるプログラムを格納した非一時的コンピュータ可読媒体（non-transitory computer readable medium）は本発明の範疇に含まれる The present invention may be applied to a system including a plurality of devices, or may be applied to a single device. Further, the present invention is also applicable to a case where an information processing program for realizing the functions of the embodiments is directly or remotely supplied to a system or an apparatus. Therefore, in order to implement the functions of the present invention on a computer, a program installed in the computer, a medium storing the program, and a WWW (World Wide Web) server for downloading the program are also included in the scope of the present invention. . In particular, at least a non-transitory computer-readable medium storing a program for causing a computer to execute the processing steps included in the above-described embodiments is included in the scope of the present invention.

Claims (12)

  1. 　金属粉末のインピーダンスを測定するインピーダンス測定ステップと、
    　前記測定されたインピーダンスから容量成分を抽出する容量成分抽出ステップと、
    　前記金属粉末の前記容量成分がゼロになる場合、前記金属粉末が予備加熱温度を下げても電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する評価ステップと、
    　を含む金属積層造形用粉末の評価方法。     An impedance measuring step of measuring the impedance of the metal powder,
    Capacitive component extraction step of extracting a capacitive component from the measured impedance,
    When the capacity component of the metal powder becomes zero, an evaluation step of evaluating that the metal powder is a powder material for metal additive manufacturing that does not cause a smoke phenomenon at the time of electron beam irradiation even if the preheating temperature is lowered,
    Evaluation method of metal additive manufacturing powder containing
  2. 　前記インピーダンス測定ステップにおいては、前記金属粉末を加熱しながら前記金属粉末のインピーダンスを測定し、
    　前記評価ステップにおいては、前記金属粉末が所定温度に達する前に前記容量成分がゼロになる場合、スモーク現象を起こさない金属積層造形用粉末材料であると評価する請求項１に記載の金属積層造形用粉末の評価方法。     In the impedance measuring step, while measuring the impedance of the metal powder while heating the metal powder,
    2. The metal additive manufacturing according to claim 1, wherein in the evaluating step, when the capacitance component becomes zero before the metal powder reaches a predetermined temperature, the metal additive manufacturing powder is evaluated as a metal additive manufacturing powder material that does not cause a smoke phenomenon. Evaluation method for powder for use.
  3. 　前記評価ステップにおいては、前記金属粉末が３００℃に達する前に前記容量成分がゼロになる場合、前記予備加熱温度を６００～５００℃に下げても電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する請求項２に記載の金属積層造形用粉末の評価方法。 In the evaluation step, when the capacitance component becomes zero before the metal powder reaches 300 ° C., the metal lamination that does not cause a smoke phenomenon at the time of electron beam irradiation even if the preheating temperature is reduced to 600 to 500 ° C. The method for evaluating a metal additive manufacturing powder according to claim 2, wherein the method is evaluated as a molding powder material.
  4. 　前記容量成分抽出ステップにおいては、インピーダンスの測定結果をCole-ColeプロットしてCole-Cole緩和型の式にフィットさせることによって、前記容量成分を抽出する請求項１乃至３のいずれか１項に記載の金属積層造形用粉末の評価方法。 4. The capacitance component extraction step according to claim 1, wherein the capacitance component is extracted by performing a Cole-Cole plot of the impedance measurement result and fitting the result to a Cole-Cole relaxation type equation. 5. Method for evaluating powder for metal additive manufacturing.
  5. 　前記金属粉末の電気抵抗を測定する電気抵抗測定ステップをさらに含み、
    　前記評価ステップにおいては、前記金属粉末の前記容量成分がゼロになり、電気抵抗率が所定値以下になる場合、電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する請求項１乃至４のいずれか１項に記載の金属積層造形用粉末の評価方法。     The method further includes an electric resistance measuring step of measuring an electric resistance of the metal powder,
    In the evaluation step, when the capacitance component of the metal powder becomes zero and the electric resistivity becomes equal to or less than a predetermined value, it is evaluated that the metal powder is a metal additive manufacturing powder material that does not cause a smoke phenomenon when irradiated with an electron beam. The method for evaluating a metal additive manufacturing powder according to claim 1.
  6. 　測定された金属粉末のインピーダンスを取得するインピーダンス取得ステップと、
    　前記取得されたインピーダンスから容量成分を抽出する容量成分抽出ステップと、
    　前記金属粉末の前記容量成分がゼロになると判定された場合、電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する評価ステップと、
    　をコンピュータに実行させる金属積層造形用粉末の評価プログラム。     An impedance obtaining step of obtaining the measured impedance of the metal powder,
    A capacitance component extraction step of extracting a capacitance component from the obtained impedance,
    When the capacity component of the metal powder is determined to be zero, an evaluation step of evaluating a metal additive manufacturing powder material that does not cause a smoke phenomenon during electron beam irradiation,
    Is a computer-executable program for evaluating metal additive manufacturing powder.
  7. 　金属粉末のインピーダンスを取得するインピーダンス取得手段と、
    　前記取得されたインピーダンスから容量成分を抽出する容量成分抽出手段と、
    　前記金属粉末の前記容量成分がゼロになると判定された場合、電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する評価手段と、
    　を備える情報処理装置。     Impedance obtaining means for obtaining the impedance of the metal powder,
    Capacitance component extraction means for extracting a capacitance component from the obtained impedance,
    When it is determined that the capacitance component of the metal powder becomes zero, an evaluation unit that evaluates to be a powder material for metal additive manufacturing that does not cause a smoke phenomenon upon irradiation with an electron beam,
    An information processing apparatus comprising:
  8. 　前記評価手段が前記金属積層造形用粉末材料であると評価しなかった場合、金属粉末の衝突を含む機械的処理または金属粉末表面の金属被覆処理を前記金属粉末に対して施すよう指示する表面処理指示手段、
    　をさらに備える請求項７に記載の情報処理装置。     If the evaluation means does not evaluate the powder as the metal additive manufacturing powder material, a surface treatment for instructing the metal powder to perform a mechanical treatment including collision of the metal powder or a metal coating treatment on the surface of the metal powder. Indicating means,
    The information processing apparatus according to claim 7, further comprising:
  9. 　金属粉末のインピーダンスを測定するインピーダンス測定ステップと、
    　前記測定されたインピーダンスから容量成分を抽出する容量成分抽出ステップと、
    　前記金属粉末の前記容量成分がゼロになる場合、電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する評価ステップと、
    　前記評価ステップにおいて、前記金属積層造形用粉末材料であるとの評価されなかった場合、前記金属粉末に対して金属粉末の衝突を含む機械的処理または金属粉末表面の金属被覆処理を施す表面処理ステップと、
    　を含む金属積層造形用粉末の製造方法。     An impedance measuring step of measuring the impedance of the metal powder,
    Capacitive component extraction step of extracting a capacitive component from the measured impedance,
    When the capacity component of the metal powder becomes zero, an evaluation step of evaluating a powder material for metal additive manufacturing that does not cause a smoke phenomenon upon irradiation with an electron beam,
    In the evaluation step, when the metal powder is not evaluated as being the metal additive manufacturing powder material, a surface treatment step of performing a mechanical treatment including collision of the metal powder on the metal powder or a metal coating treatment of the metal powder surface. When,
    A method for producing a powder for metal additive manufacturing, comprising:
  10. 　敷き詰めた金属粉末を電子ビームにより選択的に溶解および凝固させて金属積層造形物を造形する金属積層造形装置であって、
    　測定された前記金属粉末のインピーダンスを取得するインピーダンス取得手段と、
    　前記取得されたインピーダンスから容量成分を抽出する容量成分抽出手段と、
    　前記金属粉末の前記容量成分がゼロになると判定された場合、電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する評価手段と、
    　前記評価手段が前記金属積層造形用粉末材料であると評価した場合に、前記金属粉末を用いて金属積層造形物を造形する積層造形手段と、
    　を備える金属積層造形装置。     A metal additive manufacturing apparatus for selectively dissolving and solidifying the spread metal powder by an electron beam to form a metal additive product,
    Impedance obtaining means for obtaining the measured impedance of the metal powder,
    Capacitance component extraction means for extracting a capacitance component from the obtained impedance,
    When the capacity component of the metal powder is determined to be zero, an evaluation unit that evaluates to be a powder material for metal additive manufacturing that does not cause a smoke phenomenon at the time of electron beam irradiation,
    When the evaluating means evaluates the metal additive manufacturing powder material, the additive manufacturing means for shaping a metal additive using the metal powder,
    A metal additive manufacturing apparatus comprising:
  11. 　前記評価手段が前記金属積層造形用粉末材料であると評価しなかった場合、金属粉末の衝突を含む機械的処理または金属粉末表面の金属被覆処理を前記金属粉末に対して施すよう指示する表面処理指示手段、
    　をさらに備える請求項１０に記載の金属積層造形装置。     If the evaluation means does not evaluate the powder as the metal additive manufacturing powder material, a surface treatment for instructing the metal powder to perform a mechanical treatment including collision of the metal powder or a metal coating treatment on the surface of the metal powder. Indicating means,
    The metal additive manufacturing apparatus according to claim 10, further comprising:
  12. 　敷き詰めた金属粉末を電子ビームにより選択的に溶解および凝固させて金属積層造形物を造形する金属積層造形装置の制御プログラムであって、
    　測定された前記金属粉末のインピーダンスを取得するインピーダンス取得ステップと、
    　前記取得されたインピーダンスから容量成分を抽出する容量成分抽出ステップと、
    　前記金属粉末の前記容量成分がゼロになると判定された場合、電子ビームの照射時にスモーク現象を起こさない金属積層造形用粉末材料であると評価する評価ステップと、
    　前記評価ステップにおいて前記金属積層造形用粉末材料であると評価した場合に、前記金属粉末を用いて金属積層造形物を造形する積層造形ステップと、
    　をコンピュータに実行させる金属積層造形装置の制御プログラム。     A control program of a metal additive manufacturing apparatus for selectively melting and solidifying the spread metal powder with an electron beam to form a metal additive manufacturing object,
    Impedance acquisition step of acquiring the measured impedance of the metal powder,
    A capacitance component extraction step of extracting a capacitance component from the obtained impedance,
    When the capacity component of the metal powder is determined to be zero, an evaluation step of evaluating a metal additive manufacturing powder material that does not cause a smoke phenomenon during electron beam irradiation,
    In the evaluation step, when it is evaluated that the metal additive manufacturing powder material, the additive manufacturing step of modeling the metal additive using the metal powder,
    Control program for a metal additive manufacturing apparatus that causes a computer to execute the process.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115401217A (en) * 2022-10-10 2022-11-29 航发优材(镇江)增材制造有限公司 Electron beam selective powder bed preheating process parameter development method

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115533123B (en) * 2022-12-06 2023-03-28 西安赛隆增材技术股份有限公司 Method for forming three-dimensional part through additive manufacturing

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20170216915A1 (en) * 2016-02-03 2017-08-03 Grid Logic Incorporated System and method for manufacturing a part
WO2017163402A1 (en) * 2016-03-25 2017-09-28 技術研究組合次世代３Ｄ積層造形技術総合開発機構 Three-dimensional additive manufacturing device, control method for three-dimensional additive manufacturing device, and control program for three-dimensional additive manufacturing device
WO2017163404A1 (en) * 2016-03-25 2017-09-28 技術研究組合次世代３Ｄ積層造形技術総合開発機構 3d additive manufacturing device, control method for 3d additive manufacturing device, and control program for 3d additive manufacturing device
WO2018122934A1 (en) * 2016-12-26 2018-07-05 技術研究組合次世代３Ｄ積層造形技術総合開発機構 Powder for metal additive manufacturing and method for manufacturing same

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20170216915A1 (en) * 2016-02-03 2017-08-03 Grid Logic Incorporated System and method for manufacturing a part
WO2017163402A1 (en) * 2016-03-25 2017-09-28 技術研究組合次世代３Ｄ積層造形技術総合開発機構 Three-dimensional additive manufacturing device, control method for three-dimensional additive manufacturing device, and control program for three-dimensional additive manufacturing device
WO2017163404A1 (en) * 2016-03-25 2017-09-28 技術研究組合次世代３Ｄ積層造形技術総合開発機構 3d additive manufacturing device, control method for 3d additive manufacturing device, and control program for 3d additive manufacturing device
WO2018122934A1 (en) * 2016-12-26 2018-07-05 技術研究組合次世代３Ｄ積層造形技術総合開発機構 Powder for metal additive manufacturing and method for manufacturing same

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115401217A (en) * 2022-10-10 2022-11-29 航发优材(镇江)增材制造有限公司 Electron beam selective powder bed preheating process parameter development method
CN115401217B (en) * 2022-10-10 2023-07-11 航发优材(镇江)增材制造有限公司 Method for developing preheating process parameters of electron beam selective powder bed

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