CN108380871B - Nano metal powder three-dimensional printing forming method based on induction heating - Google Patents
Nano metal powder three-dimensional printing forming method based on induction heating Download PDFInfo
- Publication number
- CN108380871B CN108380871B CN201810413849.XA CN201810413849A CN108380871B CN 108380871 B CN108380871 B CN 108380871B CN 201810413849 A CN201810413849 A CN 201810413849A CN 108380871 B CN108380871 B CN 108380871B
- Authority
- CN
- China
- Prior art keywords
- powder
- nano powder
- powder feeding
- forming
- metal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000000843 powder Substances 0.000 title claims abstract description 98
- 239000002184 metal Substances 0.000 title claims abstract description 82
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 82
- 238000000034 method Methods 0.000 title claims abstract description 40
- 238000010146 3D printing Methods 0.000 title claims abstract description 34
- 230000006698 induction Effects 0.000 title claims abstract description 30
- 238000010438 heat treatment Methods 0.000 title claims abstract description 19
- 239000011858 nanopowder Substances 0.000 claims abstract description 79
- 238000002844 melting Methods 0.000 claims abstract description 54
- 230000008018 melting Effects 0.000 claims abstract description 53
- 239000000758 substrate Substances 0.000 claims abstract description 44
- 238000000465 moulding Methods 0.000 claims abstract description 40
- 238000002347 injection Methods 0.000 claims abstract description 28
- 239000007924 injection Substances 0.000 claims abstract description 28
- 230000008569 process Effects 0.000 claims abstract description 21
- 230000000694 effects Effects 0.000 claims abstract description 11
- 238000011049 filling Methods 0.000 claims abstract description 10
- 238000007711 solidification Methods 0.000 claims abstract description 7
- 230000008023 solidification Effects 0.000 claims abstract description 7
- 239000010410 layer Substances 0.000 claims description 29
- 239000002245 particle Substances 0.000 claims description 14
- 238000004519 manufacturing process Methods 0.000 claims description 10
- 238000005507 spraying Methods 0.000 claims description 9
- 230000005684 electric field Effects 0.000 claims description 8
- 239000002356 single layer Substances 0.000 claims description 8
- 239000000463 material Substances 0.000 claims description 7
- 230000005476 size effect Effects 0.000 claims description 7
- 230000000903 blocking effect Effects 0.000 claims description 6
- 239000011261 inert gas Substances 0.000 claims description 6
- 230000009471 action Effects 0.000 claims description 4
- 238000003475 lamination Methods 0.000 claims description 4
- 239000007769 metal material Substances 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 4
- 239000000126 substance Substances 0.000 claims description 4
- 229910010293 ceramic material Inorganic materials 0.000 claims description 3
- 239000002131 composite material Substances 0.000 claims description 3
- 238000001816 cooling Methods 0.000 claims description 3
- 230000003116 impacting effect Effects 0.000 claims description 3
- 230000007246 mechanism Effects 0.000 claims description 3
- 238000005086 pumping Methods 0.000 claims description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
- 238000009434 installation Methods 0.000 claims description 2
- 238000005516 engineering process Methods 0.000 description 22
- 238000005245 sintering Methods 0.000 description 7
- 238000000110 selective laser sintering Methods 0.000 description 6
- 239000000654 additive Substances 0.000 description 5
- 230000000996 additive effect Effects 0.000 description 5
- 239000013078 crystal Substances 0.000 description 5
- 230000007547 defect Effects 0.000 description 5
- 239000002105 nanoparticle Substances 0.000 description 5
- 230000008646 thermal stress Effects 0.000 description 5
- 238000009825 accumulation Methods 0.000 description 4
- 238000010894 electron beam technology Methods 0.000 description 3
- 238000001465 metallisation Methods 0.000 description 3
- 239000007787 solid Substances 0.000 description 3
- 230000035882 stress Effects 0.000 description 3
- 230000003746 surface roughness Effects 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 238000001746 injection moulding Methods 0.000 description 2
- 238000004372 laser cladding Methods 0.000 description 2
- 239000002086 nanomaterial Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 238000000149 argon plasma sintering Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000005672 electromagnetic field Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 238000001459 lithography Methods 0.000 description 1
- 238000013507 mapping Methods 0.000 description 1
- 238000010310 metallurgical process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002159 nanocrystal Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000012805 post-processing Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000007666 vacuum forming Methods 0.000 description 1
Classifications
-
- 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
- B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
-
- 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
- B22F12/00—Apparatus or devices specially adapted for additive manufacturing; Auxiliary means for additive manufacturing; Combinations of additive manufacturing apparatus or devices with other processing apparatus or devices
- B22F12/20—Cooling means
-
- 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
- B22F12/00—Apparatus or devices specially adapted for additive manufacturing; Auxiliary means for additive manufacturing; Combinations of additive manufacturing apparatus or devices with other processing apparatus or devices
- B22F12/10—Auxiliary heating means
-
- 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
- B22F12/00—Apparatus or devices specially adapted for additive manufacturing; Auxiliary means for additive manufacturing; Combinations of additive manufacturing apparatus or devices with other processing apparatus or devices
- B22F12/50—Means for feeding of material, e.g. heads
- B22F12/53—Nozzles
-
- 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
- B22F12/00—Apparatus or devices specially adapted for additive manufacturing; Auxiliary means for additive manufacturing; Combinations of additive manufacturing apparatus or devices with other processing apparatus or devices
- B22F12/50—Means for feeding of material, e.g. heads
- B22F12/55—Two or more means for feeding material
-
- 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
- B33Y10/00—Processes of additive manufacturing
-
- 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
- B33Y70/00—Materials specially adapted for additive manufacturing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
-
- 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
Abstract
The invention provides a nano metal powder three-dimensional printing forming method based on induction heating, which comprises the following steps: preparing a CAD data file of a three-dimensional printing molded part, a molded substrate, metal nano powder and a nano powder injection array plate; carrying out internal block filling on the closed contour graph of each slice layer; keeping the molding substrate and the molded part at a set temperature by heating in the vacuum molding chamber; and (3) acquiring the slice data of the current slice, controlling to open the corresponding powder feeding nozzle injection valve according to the corresponding divided small block, simultaneously generating a solidification effect along with the melting and leveling processes of the metal nano powder, and increasing the thickness of the corresponding small block by a certain thickness. The invention skillfully utilizes the process idea that the temperature of the formed substrate and the formed part is below the melting point of the block and above the melting point of the metal nano powder, does not need the high-energy beam auxiliary melting effect, and realizes the three-dimensional forming of the hyperfine and ultrahigh-speed three-dimensional parts based on the nano metal powder.
Description
Technical Field
The invention belongs to the technical field of additive manufacturing, and particularly relates to a nano metal powder three-dimensional printing forming method based on induction heating.
background
The 3D printing (additive manufacturing) technology is actually a general term for a series of rapid prototyping technologies of parts, and the basic principle thereof is lamination manufacturing, in which a rapid prototyping machine forms the cross-sectional shape of a workpiece in an X-Y plane by scanning, and performs displacement of the slice thickness intermittently at the Z coordinate, thereby finally forming a three-dimensional part. The rapid prototyping technologies in the market at present are classified into a 3DP technology, an FDM fused laminated prototyping technology, an SLA three-dimensional lithography technology, SLS selective laser sintering, a DLP laser prototyping technology, a UV ultraviolet ray prototyping technology, and the like.
since the melting point of metal is very high, a laser beam or an electron beam with high energy density is required as a heat source for a 3D printing molding technique for a metal material. With the development of science and technology and the demand of popularization and application, the direct manufacturing of metal parts by using laser additive manufacturing is more and more concerned by people. Laser additive manufacturing can be divided into the following three rapid prototyping methods: a direct metal deposition technique; selecting a laser sintering technology; and thirdly, selecting a laser melting technology.
The direct metal deposition technology is a rapid forming technology which utilizes the general rapid forming idea, adopts high-power laser to melt metal powder which is synchronously supplied, and utilizes a special nozzle to stack layer by layer on a deposition substrate to form a metal part. The essence of the direct metal deposition technology is that the three-dimensional accumulation forming of metal melt is controlled by a computer, the most serious process problem is that the cracking tendency of a laser cladding layer is obvious, and the existence of cracks can greatly reduce the compactness of a laser cladding part.
the selective laser sintering technology adopts laser beams to selectively sinter solid powder layer by layer, the laser beams move layer by layer row by line in the sintering process to carry out regional scanning, and the sintered and formed solidified layers are overlapped layer by layer to generate parts with required shapes, and the whole process comprises the steps of CAD model establishment, data processing, powder laying, sintering, post-processing and the like. In the selective laser sintering technology, in the iron powder sintering process, because the temperature of laser beams acting on powder is higher and the energy is higher, the layering of a sintering layer is easy to occur in the forming process, and thus, a spheroidization phenomenon and larger cracks are formed.
The working principle of the selective laser melting technology is similar to that of the selective laser sintering technology, and the difference is that the selective laser sintering technology is applied to powder, the powder is not completely melted, and a required forming piece is prepared in a semi-melting state. When the selective laser melting technology is applied to the powder, the powder is completely melted and solidified, so that the forming quality of a formed part is remarkably improved compared with a formed part prepared by the selective laser sintering technology.
The nano material is a material which has at least one dimension in a nano scale range (1-100 nm) in a three-dimensional space or is formed by taking the nano material as a basic unit. Research shows that the nano particles have small particle size and high specific surface free energy, so the chemical potential of the nano particles is much higher than that of a block solid under the same condition, and as a result, the melting point and the sintering temperature of the nano particles are greatly lower than those of the block solid made of the same material, and the smaller the particle size of the nano particles, the lower the melting point and the sintering temperature of the nano particles are. The melting temperature of metal nanocrystals depends not only on the crystal size but also on the dimension (shape) of the crystal. For crystals of the same dimension, the melting point decreases with decreasing crystal size; and the melting point of crystals with the same size also decreases along with the reduction of the dimensionality.
In the prior art, although various metal 3D printing technologies basically adopt metal powder as a molding raw material, the powder particle size is over 100nm, and the powder needs to be melted by irradiation of external high-energy beams (laser beams or electron beams) and then solidified for molding, which has the following disadvantages: 1) in the forming process, single or multiple high-energy beams are required to be linearly scanned, for each high-energy beam, powder on a scanning path is sequentially melted and solidified to form, and parallel forming cannot be realized essentially, so that the forming speed is low and the forming efficiency is low; 2) because the electro-optic conversion efficiency of the laser and the electron beam source is low (generally less than 20 percent), and the melting point of the metal powder is very high, the energy density required by the forming is extremely high, and the actual energy consumption is very high; 3) because the adopted micron-sized metal powder has high melting point, the process quality such as the metallurgical quality of a molten pool, the surface roughness of a formed product and the like is not high, and the defects such as residual stress accumulation, thermal stress deformation, internal thermal cracks and the like are easily generated; 4) due to the problem of thermal stress deformation, the size of the molded part is limited, otherwise, a molded part meeting the requirement of dimensional accuracy cannot be obtained.
Disclosure of Invention
aiming at the defects of the prior art, the invention provides a nano metal powder three-dimensional printing and forming method based on induction heating.
the invention is realized by the following technical scheme:
A three-dimensional printing and forming method of nano metal powder based on induction heating comprises the following steps:
(1) Preparing a CAD data file of a three-dimensional printing molded part, a molded substrate, metal nano powder and a nano powder injection array plate;
The CAD data file of the three-dimensional printing molded part is a closed contour graph data set obtained by performing three-dimensional modeling on a part to be molded and processed by adopting three-dimensional CAD software, adding an auxiliary supporting structure according to the size and the shape of the obtained three-dimensional model of the part, and then setting the layer thickness according to the traditional three-dimensional printing lamination manufacturing principle to perform layered slicing;
The upper surface of the forming substrate is a plane and is required to include a closed outline pattern of a bottommost slice of a three-dimensional printing forming part, the forming substrate is made of metal or ceramic materials, and the forming substrate is provided with a heating device with controllable temperature so as to heat the upper surface of the forming substrate and keep the upper surface within a set temperature range;
The metal nano powder is used for three-dimensional printing and forming, and is required to have a temperature size effect, and the melting point of the metal nano powder is lower than that of a forming substrate;
The nano powder injection array plate is provided with a parallel nozzle array formed by combining a plurality of powder feeding nozzles, the shape of each powder feeding nozzle requires that the cross section of a pipeline is a closed figure of any polygon or curve, and the size of the pipeline of each powder feeding nozzle requires that single metal nano powder with the largest particle size can pass through the pipeline without obstruction; each powder feeding nozzle is provided with a spraying valve for controlling the powder feeding nozzle to be closed and opened; the outgoing end of each powder feeding nozzle is provided with an induction coil, and the center of the magnetic field of the induction coil is positioned on the central axis of the outgoing end of the powder feeding nozzle; metal nano-powder is sprayed out through the center of the induction coil; the powder feeding nozzle and the induction coil are internally provided with water cooling mechanisms;
the emission end array area of all the powder feeding nozzles on the parallel nozzle array is required to be capable of including the closed contour figures of all the layered slices of the three-dimensional printing forming part;
(2) according to the parallel nozzle array arrangement relation of the nano powder injection array plate, the closed outline graph of each layer of slices is internally filled in a blocking mode, and the blocking type filling method comprises the following steps: dividing the inside of the closed contour graph into a plurality of small blocks, wherein the position of each small block is required to correspond to the position of a unique powder feeding nozzle, namely the number and the positions of the small blocks and the powder feeding nozzles are in one-to-one correspondence, and connecting lines between the mass centers of the small blocks and the geometric centers of the outlet cross sections of the powder feeding nozzles corresponding to the mass centers of the small blocks are parallel to each other; corresponding to the powder feeding nozzle, the small blocks are in the shape of any polygon or curve closed graph, the size area of each small block is required to be smaller than an area set value, the area set value is a single-layer tiled area x (1-overlapping amount) obtained after the nano powder is melted in the step (6), and the overlapping amount is 10-50%;
(3) arranging the output ports of the injection of the molding substrate and the nano powder injection array plate in a molding cavity, wherein the molding cavity is vacuum or nearly vacuum and is provided with a real-time vacuum control system for pumping air in real time to keep air pressure; the installation orientation of the nano powder injection array plate is required to ensure that the parallel nozzle array is vertical to the surface of the molded substrate and is in one-to-one correspondence with the positions of the small blocks obtained after the block type filling in the step (2), namely, the motion direction of the nano powder injected from the parallel powder feeding nozzles vertically impacts the surface of the molded substrate and is used for filling the corresponding small blocks filled in the block type in the step (2);
(4) Heating to keep the forming substrate and the formed part at a set temperature all the time in the forming process, wherein the set temperature is required to be below the melting point of the bulk and above the melting point of the metal nano powder; the bulk melting point refers to the melting point of a common bulk metal material with the same chemical composition as the metal nano powder material, namely the melting point without temperature size effect;
(5) Taking the slice at the bottommost layer of the CAD data file of the three-dimensional printing molded part as a current slice;
(6) obtaining slice data of the current slice, controlling to open a corresponding powder feeding nozzle injection valve according to the corresponding divided small block, enabling the metal nano powder to flow out through the powder feeding nozzle under the composite driving action of one or more of inert gas flow, a magnetic field or an electric field, and then heating through an induction coil to increase the temperature; then vertically impacting the current molding surface of the molding substrate, namely falling into small blocks filled in a segmented mode corresponding to the current molding surface; because the temperature of the current molding surface is higher than the melting point of the metal nano powder, the metal nano powder is quickly melted and automatically flows into the small block; because the temperature of the current forming surface is not equal to the melting point of the block body, the solidification effect is simultaneously generated along with the melting and leveling processes of the metal nano powder, namely, the metal nano powder is fused with the current forming surface into a whole through melting, leveling and solidification, and the corresponding small block is increased by a certain thickness;
(7) adjusting the relative distance between the molding substrate and the spraying output port of the nano powder spraying array plate, and taking the next slice as the current slice according to the sequence of the layered slices from bottom to top;
(8) And (5) repeating the steps (6) - (7) to realize the layer-by-layer stacking of the molded parts from the bottom to the top until all the layers are molded.
the invention has the following beneficial effects:
1) The invention utilizes the temperature size effect of the nano metal powder (the smaller the particle size of the particles, the lower the melting point and the sintering temperature of the particles), adopts the superfine nano metal powder which is not selected by the traditional method, greatly reduces the molding temperature of the metal parts, skillfully utilizes the process idea of making the temperature of the molding substrate and the molded part below the melting point of the bulk and above the melting point of the metal nano powder, does not need the high-energy beam auxiliary melting effect, and realizes the three-dimensional molding (additive manufacturing) of the superfine and ultrahigh-speed three-dimensional parts based on the nano metal powder.
2) The invention integrally heats the forming substrate and the formed part in the forming process, has no problem of temperature gradient of the forming substrate and the formed part, solves the problem of forming thermal stress caused by inevitable temperature gradient of the traditional high-energy beam scanning three-dimensional forming method, and simultaneously eliminates the defects of residual stress accumulation, thermal stress deformation, internal thermal cracks and the like.
3) The invention adopts the area array projection type powder parallel injection molding of the nanometer powder injection array plate, and one-step injection molding is carried out on any single layer, so that the molding speed is greatly improved by orders of magnitude compared with the traditional method;
4) The invention adopts the nano metal powder as the raw material, and the particle size is much smaller than that of the traditional method, so that the formed layer has high thickness precision, the surface roughness of the formed part is reduced (theoretically, the surface roughness is about half of the particle size of the formed powder, so the surface of the formed part of the nano metal powder is smoother), and the process quality is better; in addition, the molding process is in a low vacuum environment, and the problem of influence of molding environment such as oxidation and the like cannot be caused.
5) the invention can send different powder according to the need in the forming process (the powder tube adjusts the powder sending type according to time and space), thus can form any component and distributed member such as gradient material, dissimilar material, etc., it is flexible and convenient, the degree of freedom is large;
6) the invention eliminates the defects of residual stress accumulation, thermal stress deformation, internal thermal cracks and the like, so that the forming size is not limited, and the forming of large-size parts can be realized; and compared with the traditional method, the adopted nano metal powder is more suitable for three-dimensional forming of micro-nano fine parts, and the forming of conformal scaling mapping can be realized by using the magnetic control coil convergence effect, so that the forming size is further reduced, and the forming precision is improved.
7) the invention adopts the medium-high frequency electric field induction heating effect, on one hand, the preheating of the nano metal powder is realized, the rapid melting of the nano metal powder after the nano metal powder reaches the molding surface is promoted, the molding speed can be effectively improved, on the other hand, the strong alternating electric field has strong electromagnetic stirring effect on the leveling process of the metal liquid drops on the molded surface, the metallurgical process of the nano metal powder is more uniform and sufficient, the defects of internal crystallization segregation, thermal cracks and the like are favorably eliminated, and the molding quality is better.
drawings
FIG. 1 is a schematic view of a powder feeding nozzle, an induction coil and a molded substrate;
FIG. 2 is a schematic view of a grid nozzle array;
FIG. 3 is a schematic diagram of a circular tube grid nozzle array;
Detailed Description
the present invention will be described in further detail with reference to specific embodiments.
The invention provides a nano metal powder three-dimensional printing and forming method based on induction heating, which comprises the following steps:
(1) preparing a CAD data file of a three-dimensional printing molded part, a molded substrate, metal nano powder and a nano powder injection array plate;
the CAD data file of the three-dimensional printing molded part is a closed contour graph data set obtained by three-dimensionally modeling a part to be molded and processed by a designer by using three-dimensional CAD software, adding a necessary auxiliary supporting structure according to the size and the shape of the obtained three-dimensional model of the part, and then carrying out layered slicing on the set layer thickness (the single-layer tiled layer thickness after melting the nano powder) according to the traditional three-dimensional printing lamination manufacturing principle;
the upper surface of the forming substrate is a plane and is required to include a closed outline pattern of a bottommost slice of a three-dimensional printing forming part, the forming substrate is made of metal or ceramic material with good heat conductivity, and the forming substrate is provided with a heating device with controllable temperature so as to heat the upper surface of the forming substrate and keep the upper surface within a set temperature range.
preferably, the following induction coil can be adopted to heat and control the temperature in the set temperature range in real time on the real-time forming surface part of the three-dimensional printing forming part.
The metal nano powder is used for three-dimensional printing and forming, the metal nano powder is required to have a temperature size effect, the particle size of a typical forming powder is less than 100 nanometers (namely less than the particle size threshold with a temperature scale effect), and the melting point of the metal nano powder is required to be lower than that of a substrate.
Preferably, the metal nanopowder is itself magnetic or electrically charged and can be accelerated by a magnetic or electric field.
as shown in fig. 1, a parallel nozzle array formed by combining a plurality of powder feeding nozzles 1 is arranged on the nano powder injection array plate, the shape of the powder feeding nozzle 1 requires that the cross section of a pipeline is a closed figure of any polygon or curve, and the size of the pipeline of the powder feeding nozzle 1 requires that a single metal nano powder 5 with the maximum particle size can pass through the pipeline without obstruction; the shapes and the sizes of the powder feeding nozzles 1 can be the same or different; each powder feeding nozzle 1 is provided with an injection valve for controlling the closing and opening thereof, i.e., controlling whether each powder feeding nozzle 1 injects the metal nano powder 5.
An induction coil 2 is arranged at the emergent end of each powder feeding nozzle 1, and the magnetic field center of the induction coil 2 is positioned on the central axis of the emergent end of the powder feeding nozzle 1. The metal nanopowder 5 is ejected through the center of the induction coil 2. And water cooling mechanisms are arranged inside the powder feeding nozzle 1 and the induction coil 2.
the arrangement area of the emergent ends of all the powder feeding nozzles 2 on the parallel nozzle array is required to be capable of including the closed contour figures of all the layered slices of the three-dimensional printing forming part.
Typical nanopowder spray array plates are: a well-shaped grid nozzle array, a honeycomb polygon, a grid nozzle array (as shown in fig. 2), a round tube grid nozzle array (as shown in fig. 3), and the like.
after the injection valve is opened, metal powder 5 is injected from the emergent end of the powder feeding nozzle 1 through one or more compound driving actions of inert gas flow, a magnetic field or an electric field, then enters the magnetic field of the induction coil 2 and is rapidly inductively heated by the induction coil 2, and the induction coil 2 is connected with an external high-frequency or medium-frequency induction power supply.
The transport gas is required to be chemically inert to the metal powder 5 at high temperatures, typically inert gas, nitrogen, carbon dioxide or a mixture of gases.
(2) according to the parallel nozzle array arrangement relation of the nano powder injection array plate, the closed outline graph of each layer of slices is internally filled in a blocking mode, and the blocking type filling method comprises the following steps: dividing the inside of the closed contour graph into a plurality of small blocks, wherein the position of each small block is required to correspond to the position of a unique powder feeding nozzle, namely the number and the positions of the small blocks and the powder feeding nozzles are in one-to-one correspondence, and the mass centers (assumed to be equal-thickness plates with uniform density, and the mass centers exist certainly) of the small blocks are parallel to the connecting line between the geometric centers of the outlet cross sections of the powder feeding nozzles corresponding to the mass centers; and (3) corresponding to the powder feeding nozzle, wherein the small blocks are in the shape of any polygon or curve closed graph, the size area of each small block is required to be smaller than an area set value, the area set value is the single-layer tiled area x (1-overlapping amount) after the nano powder is melted in the step (6), and the overlapping amount is 10-50%. Wherein, the single-layer flat pavement thickness after the melting of the nano powder in the step (6) and the single-layer flat pavement thickness after the melting of the nano powder in the step (1) can be measured in advance through an experimental method.
(3) arranging the forming substrate 3 and the output port of the nano powder injection array plate in a forming cavity, wherein the forming cavity is vacuum or nearly vacuum (the air pressure is less than 100 pascals), and the forming cavity is provided with a real-time vacuum control system which can pump air in real time to keep extremely low air pressure (less than 100 pascals); since the jet driving force of the metal nanopowder is an inert gas or an electromagnetic field, real-time pumping is required.
The nano powder injection array plate is required to be installed in an orientation that the parallel nozzle array is perpendicular to the surface of the molding substrate 3 and is in one-to-one correspondence with the positions of the small blocks obtained after the block type filling in the step (2), namely, the motion direction of the nano powder injected through the parallel powder feeding nozzles perpendicularly impacts the surface of the molding substrate and is used for filling the corresponding small blocks filled in the block type in the step (2).
Preferably, the molding direction (the movement direction of the nanopowder ejected through the parallel powder feeding nozzle) is vertical to the gravity, so as to avoid the gravity deflection effect.
Preferably, the vacuum forming chamber is subjected to vibration isolation treatment so that the vibration amplitude is not greater than the forming dimensional accuracy.
(4) The forming substrate 3 and the formed part 4 are always kept at a set temperature in the forming process through heating, and the set temperature is required to be below the melting point of the bulk and above the melting point of the metal nano powder; the bulk melting point refers to the melting point of a common bulk metal material with the same chemical composition as the metal nano powder material, namely the melting point without temperature size effect.
(5) Taking the slice at the bottommost layer of the CAD data file of the three-dimensional printing molded part as a current slice;
(6) Obtaining slice data of the current slice, controlling to open a corresponding powder feeding nozzle injection valve according to the corresponding divided small block, enabling the metal nano powder to flow out through the powder feeding nozzle under the composite driving action of one or more of inert gas flow, a magnetic field or an electric field, and then heating through an induction coil to increase the temperature; then vertically impacting the current molding surface of the molding substrate, namely falling into small blocks filled in a segmented mode corresponding to the current molding surface; because the temperature of the current molding surface is higher than the melting point of the metal nano powder, the metal nano powder is quickly melted and automatically flows into the small block; because the temperature of the current forming surface is not equal to the melting point of the block body, the solidification effect is simultaneously generated along with the melting and leveling processes of the metal nano powder, namely, the metal nano powder is fused with the current forming surface into a whole through melting, leveling and solidification, and the corresponding small block is increased by a certain thickness;
Preferably, the output and the closing of the area array type parallel powder feeding nozzle injection valve of the nano powder injection array plate can be controlled by adopting the LCD liquid crystal panel display control principle similar to the structural principle of the nano powder injection array plate.
preferably, if the metal nanopowder itself is magnetic or electrically charged, a magnetic or electric field may be applied to accelerate it after the powder delivery nozzle 1 has flowed out until it hits the forming surface.
(7) adjusting the relative distance between the molding substrate 3 and the spraying output port of the nanopowder spraying array plate (i.e. moving a single-layer molding layer thickness to keep the two not touching and within a proper spraying molding distance range), and taking the next slice as the current slice according to the sequence of the layered slices from bottom to top.
(8) And (5) repeating the steps (6) - (7) to realize the layer-by-layer stacking of the molded parts from the bottom to the top until all the layers are molded.
It will be obvious to those skilled in the art that the present invention may be varied in many ways, and that such variations are not to be regarded as a departure from the scope of the invention. All such modifications as would be obvious to one skilled in the art are intended to be included within the scope of this claim.
Claims (1)
1. a three-dimensional printing and forming method of metal nano powder based on induction heating is characterized by comprising the following steps:
(1) Preparing a CAD data file of a three-dimensional printing molded part, a molded substrate, metal nano powder and a nano powder injection array plate;
The CAD data file of the three-dimensional printing molded part is a closed contour graph data set obtained by performing three-dimensional modeling on a part to be molded and processed by adopting three-dimensional CAD software, adding an auxiliary supporting structure according to the size and the shape of the obtained three-dimensional model of the part, and then setting the layer thickness according to the traditional three-dimensional printing lamination manufacturing principle to perform layered slicing;
the upper surface of the forming substrate is a plane and is required to include a closed outline pattern of a bottommost slice of a three-dimensional printing forming part, the forming substrate is made of metal or ceramic materials, and the forming substrate is provided with a heating device with controllable temperature so as to heat the upper surface of the forming substrate and keep the upper surface within a set temperature range;
The metal nano powder is used for three-dimensional printing and forming, and is required to have a temperature size effect, namely the particle size of the metal nano powder is less than 100 nanometers, and the melting point of the metal nano powder is lower than that of a forming substrate;
the nano powder injection array plate is provided with a parallel nozzle array formed by combining a plurality of powder feeding nozzles, the shape of each powder feeding nozzle requires that the cross section of a pipeline is a closed figure of any polygon or curve, and the size of the pipeline of each powder feeding nozzle requires that single metal nano powder with the largest particle size can pass through the pipeline without obstruction; each powder feeding nozzle is provided with a spraying valve for controlling the powder feeding nozzle to be closed and opened; the outgoing end of each powder feeding nozzle is provided with an induction coil, and the center of the magnetic field of the induction coil is positioned on the central axis of the outgoing end of the powder feeding nozzle; metal nano-powder is sprayed out through the center of the induction coil; the powder feeding nozzle and the induction coil are internally provided with water cooling mechanisms;
The emission end array area of all the powder feeding nozzles on the parallel nozzle array is required to be capable of including the closed contour figures of all the layered slices of the three-dimensional printing forming part;
(2) According to the parallel nozzle array arrangement relation of the nano powder injection array plate, the closed outline graph of each layer of slices is internally filled in a blocking mode, and the blocking type filling method comprises the following steps: dividing the inside of the closed contour graph into a plurality of small blocks, wherein the position of each small block is required to correspond to the position of a unique powder feeding nozzle, namely the number and the positions of the small blocks and the powder feeding nozzles are in one-to-one correspondence, and the connecting lines between the mass centers of the small blocks and the geometric centers of the outlet cross sections of the powder feeding nozzles corresponding to the mass centers of the small blocks are parallel to each other; the shape of the small blocks corresponding to the powder feeding nozzle is any polygon or curve closed graph, the size area of each small block is required to be smaller than an area set value, the area set value is a single-layer tiled area x (1-overlapping amount) of the powder feeding nozzle after the powder is sprayed once and the nano powder is melted, and the overlapping amount is 10-50%;
(3) arranging the output ports of the injection of the molding substrate and the nano powder injection array plate in a molding cavity, wherein the molding cavity is vacuum or nearly vacuum and is provided with a real-time vacuum control system for pumping air in real time to keep air pressure; the installation orientation of the nano powder injection array plate is required to ensure that the parallel nozzle array is vertical to the surface of the molded substrate and is in one-to-one correspondence with the positions of the small blocks obtained after the block type filling in the step (2), namely, the motion direction of the nano powder injected from the parallel powder feeding nozzles vertically impacts the surface of the molded substrate and is used for filling the corresponding small blocks filled in the block type in the step (2);
(4) heating to keep the forming substrate and the formed part at a set temperature all the time in the forming process, wherein the set temperature is required to be below the melting point of the bulk and above the melting point of the metal nano powder; the bulk melting point refers to the melting point of a common bulk metal material with the same chemical composition as the metal nano powder material, namely the melting point without temperature size effect;
(5) taking the slice at the bottommost layer of the CAD data file of the three-dimensional printing molded part as a current slice;
(6) Obtaining slice data of the current slice, controlling to open a corresponding powder feeding nozzle injection valve according to the corresponding divided small block, enabling the metal nano powder to flow out through the powder feeding nozzle under the composite driving action of one or more of inert gas flow, a magnetic field or an electric field, and then heating through an induction coil to increase the temperature; then vertically impacting the current molding surface of the molding substrate, namely falling into small blocks filled in a segmented mode corresponding to the current molding surface; because the temperature of the current molding surface is higher than the melting point of the metal nano powder, the metal nano powder is quickly melted and automatically flows into the small block; because the temperature of the current forming surface is not equal to the melting point of the block body, the solidification effect is simultaneously generated along with the melting and leveling processes of the metal nano powder, namely, the metal nano powder is fused with the current forming surface into a whole through melting, leveling and solidification, and the corresponding small block is increased by a certain thickness;
(7) adjusting the relative distance between the molding substrate and the spraying output port of the nano powder spraying array plate, and taking the next slice as the current slice according to the sequence of the layered slices from bottom to top;
(8) And (5) repeating the steps (6) - (7) to realize the layer-by-layer stacking of the molded parts from the bottom to the top until all the layers are molded.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810413849.XA CN108380871B (en) | 2018-05-03 | 2018-05-03 | Nano metal powder three-dimensional printing forming method based on induction heating |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810413849.XA CN108380871B (en) | 2018-05-03 | 2018-05-03 | Nano metal powder three-dimensional printing forming method based on induction heating |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108380871A CN108380871A (en) | 2018-08-10 |
| CN108380871B true CN108380871B (en) | 2019-12-10 |
Family
ID=63066166
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810413849.XA Active CN108380871B (en) | 2018-05-03 | 2018-05-03 | Nano metal powder three-dimensional printing forming method based on induction heating |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108380871B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111515397B (en) * | 2020-05-06 | 2022-06-10 | 中国航空制造技术研究院 | Design method and use method of additive manufacturing surface heat source |
| CN112848286A (en) * | 2020-12-31 | 2021-05-28 | 天津大学 | Multi-material powder additive manufacturing system and manufacturing method |
| CN113355669B (en) * | 2021-06-04 | 2023-05-23 | 华中科技大学 | Ultra-high-speed reinforcing phase particle uniform distribution device in metal matrix composite forming |
| CN114818248B (en) * | 2022-01-12 | 2023-10-10 | 四川大学 | Model slice processing method for additive manufacturing |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101092634B1 (en) * | 2009-11-20 | 2011-12-13 | 한국생산기술연구원 | Low temperature sintering method of high melting point rare metal and high melting point rare metal compact manufactured by method thereof |
| KR20120136227A (en) * | 2011-06-08 | 2012-12-18 | 한국생산기술연구원 | Low temperature sintering method of high melting point metal and high melting point metal compact manufactured by method thereof |
| CN103611939A (en) * | 2013-11-28 | 2014-03-05 | 宁波金鹏高强度紧固件有限公司 | Method for manufacturing abrasion-resistant fastening piece through 3D printing technology |
| CN104910685B (en) * | 2014-03-10 | 2017-09-26 | 中国科学院化学研究所 | Can room temperature sintering inkjet printing conductive ink and its application |
| US20160096326A1 (en) * | 2014-10-03 | 2016-04-07 | Tyco Electronics Corporation | Selective zone temperature control build plate |
| CN104877464A (en) * | 2015-05-08 | 2015-09-02 | 哈尔滨工业大学深圳研究生院 | Composite nano silver particle conductive ink and preparation method and printing application thereof |
-
2018
- 2018-05-03 CN CN201810413849.XA patent/CN108380871B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN108380871A (en) | 2018-08-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108555301B (en) | Partitioned parallel three-dimensional printing forming method for large precise metal parts | |
| CN108405863B (en) | Parallel metal three-dimensional printing forming method based on induction melting | |
| CN108380871B (en) | Nano metal powder three-dimensional printing forming method based on induction heating | |
| TWI511823B (en) | Apparatus and method for controlling the additive manufacturing | |
| JP6898036B2 (en) | Additional manufacturing using mobile scanning area | |
| Wang et al. | Research on the fabricating quality optimization of the overhanging surface in SLM process | |
| CN106965421B (en) | Three-dimensional printing method | |
| JP2020506826A (en) | Additive manufacturing using a mobile scanning area | |
| JP2020506824A (en) | Additive manufacturing using a mobile scanning area | |
| CN104028761B (en) | The micro-spray fusing of a kind of metal drips electromagnetic confinement deposition modeling system | |
| CN110214075A (en) | Material is preheated in increasing material manufacturing equipment | |
| US20130287934A1 (en) | Liquid Metal Digital Manufacturing System | |
| EP2962789A2 (en) | Additive manufacturing methods and systems with fiber reinforcement | |
| CN104086184B (en) | The method of the clean shaped ceramic part of a kind of ultrasonic wave added Laser Near | |
| EP3476504B1 (en) | Applying electric pulses through a laser induced plasma channel for use in a 3-d metal printing process | |
| CN104010749A (en) | Method and apparatus for producing three-dimensional objects | |
| EP3096906A1 (en) | Additive manufacturing system and method of operation | |
| JP2017075362A (en) | Method for manufacturing three-dimensional molded object and apparatus for manufacturing three-dimensional molded object | |
| CN108748975A (en) | A kind of nano high-precision increasing material manufacturing equipment | |
| US20190134891A1 (en) | Dmlm build platform and surface flattening | |
| CN104785786B (en) | One kind send paddle metal parts increasing material manufacturing method and device | |
| CN108015286B (en) | High-entropy alloy droplet ejection additive manufacturing device and method | |
| CN108607995B (en) | A kind of metal 3 D-printing forming method based on nano temperature dimensional effect | |
| JP2020505509A (en) | Additive manufacturing using a mobile scanning area | |
| CN108405864B (en) | Direct-writing type metal three-dimensional printing forming method based on induction melting |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20220627 Address after: No. 58, Gongye North Road, Licheng District, Jinan City, Shandong Province Patentee after: SHANDONG CHENGKUN INFORMATION TECHNOLOGY CO.,LTD. Address before: 325000 Wenzhou City National University Science Park incubator, No. 38 Dongfang South Road, Ouhai Economic Development Zone, Wenzhou, Zhejiang Patentee before: WENZHOU VOCATIONAL & TECHNICAL College |
|
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20230508 Address after: Unit 202 and 203, Building 1, Chuangqi, No. 63, Chuangqi Road, Shilou Town, Panyu District, Guangzhou City, Guangdong Province, 510000 Patentee after: Hongfan (Guangzhou) Intelligent Technology Co.,Ltd. Address before: No. 58, Gongye North Road, Licheng District, Jinan City, Shandong Province Patentee before: SHANDONG CHENGKUN INFORMATION TECHNOLOGY CO.,LTD. |