JP2011202201A - Method for producing metal sintered compact and production device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production device and method which suppress the generation of the deformation caused by a temperature difference between the end part in the width direction and the central part in the production of a sheet-shaped sintered compact by energizing pressure sintering with rolls.SOLUTION: The device for producing the sheet-shaped sintered compact includes at least a pair of power feed rolls 3a, 3b running a sheet-shaped molded body F, and arranged at intervals in the running direction of the sheet-shaped molded body F; a power feed mechanism 5 feeding electric current to the sheet-shaped molded body F via a pair of the power feed rolls 3a, 3b; and press rolls arranged so as to be confronted with a pair of the power feed rolls 3a, 3b, and holding the sheet-shaped molded body F between the power feed rolls 3a, 3b. In a pair of the power feed rolls 3a, 3b, both the end parts of the respective power feed rolls 3a, 3b are connected in parallel to the power source feed part 50 of the power feed mechanism 5, and the power feed mechanism is provided with an energizing control part 52 switching the energizing connection between the power feed part 50 and both the end parts of the power feed rolls 3a, 3b in such a manner that the end part in the width direction of the sheet-shaped molded body F is highly energized than the central part in the width direction.

Description

  The present invention relates to a manufacturing apparatus suitable for a method of manufacturing a sintered metal body made of titanium, stainless steel, Ni-base alloy or the like.

  As a method for producing a metal sintered body, for example, as described in Patent Document 1, an organic binder, a plasticizer, water, a surfactant and the like are mixed with metal powder to form a slurry, and this slurry is formed. The one which heat-sinters the formed compact is proposed. When sintering a compact made of such a slurry, the compact is charged into a sintering furnace and heated in the sintering furnace with a heater or burner to increase the atmosphere temperature of the sintering furnace. The body is heated and sintered. Therefore, in order to heat the compact itself to a predetermined temperature, it is necessary to keep the entire internal atmosphere of the sintering furnace at a high temperature for a relatively long time, which has a problem of poor thermal efficiency.

  Moreover, in order to perform sintering efficiently, in patent document 2, the molded object shape | molded in plate shape with a pair of rolling roll is passed between two or more pairs of electric power supply rolls, and a pressing roll, and it supplies with electricity. A method of heating and sintering has been proposed. In Patent Document 2, since the molded body itself is heated and sintered by energization, it can be heated in a short time and heat efficiency is good. Moreover, since it can sinter while conveying a molded object, a molded object can be continuously heat-sintered and it is efficient.

  However, such a compact shrinks in the width direction, the traveling direction, and the thickness direction as the sintering proceeds. Moreover, since heat is easily diffused at the width direction end portion of the molded body, the temperature tends to be lower than that of the width direction center portion. For this reason, the shrinkage rate of the width direction end portion is small, and the shrinkage rate of the width direction center portion is large, and the width direction end portion of the molded body is deformed so as to wave, or the molded body is meandering. You may run. When such deformation or meandering occurs, there is a risk that the manufactured metal sintered body will be cracked and cut, or the power supply roll may be damaged. And if electricity supply with a feed roll and a molded object is not performed uniformly by deformation | transformation, it will become easy to generate | occur | produce a spark because a large current passes locally. In addition, the surface of the power supply roll may be melted by the spark, or the surface may be scratched to form irregularities, which may impede uniform energization and induce further sparks.

JP 2007-046089 A Japanese Patent No. 30608003

  This invention is made | formed in view of such a situation, and provides the manufacturing apparatus suitable for the manufacturing method of the metal sintered compact which can manufacture a metal sintered compact efficiently using a feed roll. To do.

  An apparatus for producing a sintered metal body according to the present invention is an apparatus for producing a sintered metal body in which a sheet-like molded body made of metal powder is energized and sintered by self-heating, and travels through the sheet-like molded body. And at least a pair of power supply rolls arranged at intervals in the traveling direction of the sheet-shaped molded body, a power supply mechanism for supplying a current to the sheet-shaped molded body via the pair of power supply rolls, and the pair of power supply rolls A pressing roll disposed opposite the power supply roll and sandwiching the sheet-shaped molded body between the power supply roll, and the pair of power supply rolls are configured to supply power to the power supply mechanism at both ends of each power supply roll. Are connected in parallel with each other, and the power supply mechanism switches the power supply connection between the power supply unit and both ends of the power supply roll, and is wider than the widthwise center of the sheet-like molded body. Wherein the power supply controller to increase current to the end portion.

In this manufacturing apparatus, since the sheet-shaped molded body is configured to self-heat by supplying current to the sheet-shaped molded body to be heated through a pair of power supply rolls, the sheet-shaped molded body is heated in a short time. And can be sintered.
Moreover, since heat is easily diffused at the widthwise end of the sheet-like molded body, the temperature tends to be lower than that at the widthwise center. However, in the manufacturing apparatus of the present invention, the power supply unit and the both ends of the pair of power supply rolls are switched to each other, so each power supply roll located at one end in the width direction of the sheet-like molded body. By switching between the case where the end portions of the power supply rolls are connected in parallel with the running direction and the case where the end portions of the respective power supply rolls are connected diagonally to each other, the sheet-like molded body is switched. The sheet-shaped molded body can be heated uniformly by energizing the end part more than the center part in the width direction. Thereby, the temperature difference of the center part and edge part of a sheet-like molded object can be made small, and the deformation | transformation of the sheet-like molded object which arises by a temperature difference can be suppressed. Further, by preventing the deformation of the sheet-like molded body in this way, it is possible to prevent the occurrence of cracks and the like of the sintered metal body. A metal molded body can be obtained.

Moreover, the manufacturing apparatus of the metal sintered compact of this invention WHEREIN: It is good to provide the control mechanism which controls the circumferential speed of a pair of said electric power feeding roll each independently.
In this case, according to the shrinkage in the traveling direction accompanying the sintering of the sheet-like molded body, it becomes possible to adjust the peripheral speed of the power supply roll arranged on the carry-out side and the power supply roll arranged on the carry-in side, In a state where tensile stress is applied to the sheet-like molded body, the sheet-like molded body can be energized and sintered through a pair of power supply rolls. Therefore, the deformation of the sheet-like molded body accompanying the progress of sintering can be suppressed, and the metal sintered body can be produced efficiently.

In addition, a cooling pipe may be formed inside the power supply roll and the pressing roll, and a cooling mechanism may be provided that cools the refrigerant through the cooling pipe.
When the sheet-like molded body self-heats, the power supply roll and the pressing roll that are in contact with the sheet-like molded body also have a high temperature. Therefore, by providing a cooling mechanism, it is possible to prevent deterioration of the power supply roll and the pressing roll.

Moreover, the manufacturing method of the metal sintered compact of this invention is characterized by sintering a sheet-like molded object using the manufacturing apparatus of the above-mentioned metal sintered compact.
In addition, the method for producing a sintered metal body of the present invention causes a sheet-like molded body made of metal powder to travel and energizes the sheet-shaped molded body between a pair of power supply rolls arranged at intervals in the traveling direction. A method of manufacturing a sintered metal body sintered by self-heating,
Parallel energization that connects between both ends of the pair of power supply rolls along the running direction of the sheet-like molded body and energizes the widthwise ends of the sheet-like molded body, and both ends of the pair of power supply rolls The sheet-shaped molded body is energized while switching between diagonal energization that is connected in a diagonal direction and energized.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing apparatus of the metal sintered compact suitable for the manufacturing method of the metal sintered compact which can manufacture a metal sintered compact efficiently using a feed roll can be provided.

It is a flowchart which shows the manufacturing method of the metal sintered compact manufactured by this invention. In the manufacturing method of the metal sintered compact shown in FIG. 1, it is a schematic explanatory drawing of the sheet forming machine which shape | molds a sheet-like molded object. It is a schematic explanatory drawing which shows the manufacturing apparatus of the metal sintered compact of 1st Embodiment of this invention. It is explanatory drawing seen from the direction orthogonal to the running direction of the sheet-like molded object of the manufacturing apparatus shown in FIG. It is a figure explaining the electricity supply method of a sheet-like molded object. It is a figure explaining the electricity supply method of the sheet-like molded object in the manufacturing apparatus of the metal sintered compact of 2nd Embodiment of this invention.

Hereinafter, an embodiment of a metal sintered body manufacturing apparatus of the present invention will be described with reference to the drawings.
The apparatus for producing a sintered metal body according to this embodiment is for producing a sintered body of porous titanium used as a filter or the like, for example.
First, the manufacturing method of the metal sintered body (porous titanium sintered body) which is this embodiment is demonstrated for every process with reference to the flowchart shown in FIG.

(Slurry production process S1)
In the slurry preparation step S1, an organic binder, a foaming agent, a plasticizer, water and, if necessary, a surfactant are mixed with titanium powder, titanium hydride powder, or a mixed powder thereof to prepare a foamable slurry. .
In this embodiment, a mixed powder of titanium hydride powder having an average particle diameter of 5 to 30 μm and pure titanium powder having an average particle diameter of 10 to 30 μm obtained by dehydrogenating the titanium hydride powder is used as a raw material powder. Using.
Water-soluble methylcellulose or polyvinyl alcohol was used as the organic binder to which the mixed powder was bound. Neopentane, hexane and peptane were used as blowing agents. And glycerin was used as a plasticizer, and alkylbenzene sulfonate was used as a surfactant.
These raw materials are mixed powder: 5 to 80% by mass, organic binder: 0.05 to 10% by mass, foaming agent: 0.05 to 10% by mass. A plasticizer: 0.1 to 15% by mass, a surfactant: 0.05 to 5% by mass, and a mixture of water and the remainder were mixed to prepare a slurry.

  Next, a foamable sheet-like molded product F is formed from this slurry. Here, the molding step S2 and the foaming step S3 are performed using a sheet molding machine 90 shown in FIG. The sheet forming machine 90 includes a carrier sheet 92 driven by a conveying roller 91, a slurry storage portion 93 in which the slurry S is stored, a doctor blade 94 disposed on the carrier sheet 92, a foaming tank 95, and a drying tank. And a chamber 96.

(Molding step S2)
In the molding step S2, the slurry S is supplied from the slurry reservoir 93 onto the carrier sheet 92 using the sheet molding machine 90 shown in FIG. 2, and the doctor blade 94 sets the thickness of the slurry S on the carrier sheet 92 to a predetermined value. To produce a sheet slurry having a width of 110 mm, a length of 200 mm, and a thickness of 1.5 mm.

(Foaming step S3)
In the foaming step S3, the sheet-like slurry is inserted into the foaming tank 95 together with the carrier sheet 92, held at a temperature of 70 ° C. and a humidity of 90 ° C. for 1 hour, and warm air of 80 ° C. is blown in the drying chamber 96 for 1 hour. Dry with warm air. By the foaming step S3, the foaming agent in the sheet-like slurry is foamed to have a three-dimensional network structure, and a foamed molded body in which titanium powder is located in the skeleton portion of the network structure is produced.

(Degreasing step S4)
The aforementioned foamed molded body is separated from the carrier sheet 92 and placed on a support plate made of zirconia, charged in a degreasing furnace, and placed in a vacuum atmosphere of 5 × 10 ⁻² Pa at 550 ° C. Hold for 5 hours. Thereby, the fat (an organic binder etc.) contained in a foaming molding is volatilized and removed. In the foamed molded product in this state, the titanium powders are not bonded to each other and have no electrical conductivity. In addition, reaction of the titanium in a foaming molding and a support plate is prevented by using the support plate made from a zirconia.

(Pre-sintering step S5)
The degreased foamed molded product is charged into the pre-sintering furnace together with the support plate. In the pre-sintering furnace, the degreased foamed molded body is held at 800 to 1000 ° C. for 1 to 30 minutes in a vacuum atmosphere of 5 × 10 ⁻³ Pa. Thereby, the titanium powder located in the frame | skeleton part of a three-dimensional network structure couple | bonds together, and the sheet-like molded object F which has electroconductivity is produced. Here, the electrical resistance value P of the sheet-like molded body F is adjusted within a range of 20 × 10 ⁻⁶ Ω · m ≦ P ≦ 1500 × 10 ⁻⁶ Ω · m. In this embodiment, P = 100 × It is set to 10 ⁻⁶ Ω · m.

(Cutting step S6)
In the cutting step S6, the width end portion of the sheet-like molded body F produced by heating and sintering in the pre-sintering furnace is cut along the longitudinal direction, and the width is set to a predetermined length (100 mm in this embodiment). adjust. Here, in the sheet-like molded body F sintered to a degree having conductivity, the titanium powders are bonded with a certain strength, so that they do not collapse even when separated from the support plate, and easily It becomes possible to handle.

(Electrical sintering process S7)
The sheet-like molded body F separated from the support plate is subjected to current sintering using the metal sintered body manufacturing apparatus 1 shown in FIGS. 3 and 4. Specifically, an electric current is supplied to the sheet-shaped molded body F, the sheet-shaped molded body F is self-heated by Joule heat, and held at 1300 ° C. for 1 to 5 minutes in an Ar gas atmosphere.

The metal sintered body manufacturing apparatus 1 used in the electric current sintering step S7 will be described with reference to FIGS.
As shown in FIG. 3, the metal sintered body manufacturing apparatus 1 includes a sintering chamber 2 having a carry-in port 2 a and a carry-out port 2 b, and a first chamber disposed on the carry-in port 2 a side in the sintering chamber 2. A first feeding roll 3a, a first pressing roll 4a disposed opposite to the upper portion of the first feeding roll 3a, a second feeding roll 3b disposed on the side of the carry-out port 2b in the sintering chamber 2, and the second A second presser roll 4b disposed opposite to the upper portion of the power supply roll 3b, and a power supply mechanism 5 that supplies current to the sheet-like molded body F via the first power supply roll 3a and the second power supply roll 3b are provided.

As shown in FIG. 4, the first power supply roll 3 a and the second power supply roll 3 b are extended in a horizontal direction orthogonal to the traveling direction of the sheet-like molded body F (the direction indicated by the arrow A in FIG. 3). Both ends thereof are projected outside the sintering chamber 2.
A power supply connector 32 for supplying a current from the power supply mechanism 5 is provided at portions protruding from the sintering chamber 2 at both ends of the first power supply roll 3 a and the second power supply roll 3 b. In addition, cooling water is supplied to one end (on the right side in FIG. 4) of the first power supply roll 3a and the second power supply roll 3b through a water cooling pipe 33 provided inside the first power supply roll 3a and the second power supply roll 3b. A cooling water supply unit 34 for driving, a drive motor 35 for rotationally driving the first power supply roll 3a and the second power supply roll 3b, and an insulating member 36 for preventing energization between the drive motor 35 and the power supply connector 32. And are provided.

  Moreover, as shown in FIG. 4, the 1st electric power supply roll 3a and the 2nd electric power supply roll 3b are made into the double tube structure by which the water cooling piping 33 was provided in the inside. The cooling water supply unit 34 is provided with a supply pipe 34 a and a discharge pipe 34 b, and cooling water is supplied from the supply pipe 34 a to the water cooling pipe 33. The cooling water supplied toward one side (the left side in FIG. 4) of the first power supply roll 3 a and the second power supply roll 3 b through the water cooling pipe 33 passes through the annular space outside the water cooling pipe 33 and the first power supply roll 3 a and the first power supply roll 3 a. It distribute | circulates toward the other side (right side in FIG. 4) of 2 electric power feeding rolls 3b, and is discharged | emitted outside via the discharge pipe 34b.

The power supply connector 32 is a cylindrical member (slip ring) provided on the outer peripheral surface of the rotating first power supply roll 3a and the second power supply roll 3b, and the power supply connector 32 is provided with an electrode 51 such as a carbon brush. Thus, a current is supplied from the power supply unit 50 of the power supply mechanism 5. In the present embodiment, the power supply unit 50 is a DC power source.
For example, a coupling made of an insulating resin is used for the insulating member 36.

Moreover, both ends of the first power supply roll 3a and the second power supply roll 3b are connected in parallel to the power supply unit 50 via switches s1 to s4 as shown in FIG. By switching on / off of these switches s1 to s4 and changing the combination of the ends of the two power supply rolls 3a and 3b, the energization direction of the sheet-like molded body F can be switched.
The power supply mechanism 5 is provided with an energization control unit 52 that controls switching of energization connections of the switches s1 to s4. The energization control unit 52 controls the heat generation of the sheet-shaped molded body F by continuously switching the energization direction of the sheet-shaped molded body F by continuously switching the energization connection of the switches s1 to s4 every short time. To do.

  Both ends of the first pressing roll 4a and the second pressing roll 4b are supported by a pair of support arms 40 provided so as to penetrate the ceiling portion of the sintering chamber 2, as shown in FIG. Has been. The support arm 40 is provided with an insulator 41 so as to divide the midway position.

Each of the support arms 40 is supported by a pressure adjustment mechanism 8 installed at the upper part of the ceiling portion of the sintering chamber 2, and can be configured to adjust the vertical position of the first pressing roll 4a and the second pressing roll 4b. Has been. That is, the pressure adjusting mechanism 8 is configured to adjust the holding pressure between the first power supply roll 3a and the first pressing roll 4a and the holding pressure between the second power supply roll 3b and the second pressing roll 4b. In addition, a load cell 42 is attached to the support arm 40 in order to detect the clamping pressure.
A viewing window 21 is provided at the center of the ceiling of the sintering chamber 2, and a radiation thermometer 22 is supported on the outside of the viewing window 21 so as to be movable in the width direction of the sheet-like molded body F. With this radiation thermometer 22, the temperature distribution of the sheet-like molded body F can be measured from the outside of the sintering chamber 2.

  In addition, the first pressing roll 4a and the second pressing roll 4b have a double-pipe structure in which a water-cooled pipe 43 is provided inside, similar to the first feeding roll 3a and the second feeding roll 3b described above. The cooling water is supplied by circulating the cooling water through the cooling water supply means 44.

  The installation interval between the first pressing roll 4a and the second pressing roll 4b and the installation interval between the first feeding roll 3a and the second feeding roll 3b are, for example, 100 mm. The roll interval is determined in consideration of the heating time required for the product (which varies depending on the material and application) and the production speed.

Furthermore, these 1st electric power supply roll 3a and the 2nd electric power supply roll 3b, the 1st press roll 4a, and the 2nd press roll 4b are comprised by the material with small thermal expansion coefficients, such as a tungsten alloy, for example.
And the 1st electric power feeding roll 3a and the 2nd electric power feeding roll 3b are provided with control part 37a, 37b which controls each peripheral speed independently. The first pressing roll 4a and the second pressing roll 4b are driven rolls that follow the first feeding roll 3a and the second feeding roll 3b.

Next, a method for electrically sintering the sheet-like formed body F by the metal sintered body manufacturing apparatus 1 configured as described above will be described.
First, the sheet-like molded body F is sandwiched between the first power supply roll 3a and the first pressing roll 4a, and is also sandwiched between the second power supply roll 3b and the second pressing roll 4b. And the 1st electric power supply roll 3a and the 2nd electric power supply roll 3b are driven, and the sheet-like molded object F is conveyed. At this time, the sheet-shaped molded body F is energized from the power supply mechanism 5 through the first power supply roll 3a and the second power supply roll 3b.

The energization of the sheet-shaped molded body F is the current flowing through the sheet-shaped molded body F by switching on and off the switches s1 to s4 at the end of the first power supply roll 3a and the second power supply roll 3b. Change the direction. At this time, heat is easily diffused at the end in the width direction of the sheet-like molded body F, and the temperature tends to be lower than that at the center in the width direction. By increasing the number of patterns energized at both ends in the width direction of the body F, the temperature difference between the central portion and the end portion of the sheet-like molded body F is controlled to be small.
Table 1 shows a combination (energization pattern) of the connection states of the switches s1 to s4 and the energization direction of the current flowing through the sheet-like molded body F corresponding to this combination. The “energization direction” in Table 1 indicates the energization direction of the sheet-like molded body F using arrows c1 to c4 shown in FIG.

For example, in the energization pattern 1 of Table 1, the switches s1 and s3 are “ON”, and the switches s2 and s4 are “OFF”, and the sheet-shaped molded body F travels between the widthwise ends. In this state, a large amount of current flows in the direction c1 connected along the line. This energization state is called parallel energization.
Further, in the energization pattern 2, the switches s1 and s4 are “ON” and the switches s2 and s3 are “OFF”, and the first power supply roll 3a and the second power supply roll located at the opposite end of the first power supply roll 3a. A large amount of current flows in a diagonal direction c2 connecting one end of 3b. This energization state is called diagonal energization.
The energization patterns 1 and 4 are parallel energization in which more energization is applied to both end portions in the width direction than the center portion in the width direction of the sheet-like molded body F. The energization patterns 2 and 3 are diagonal energization in which a large amount of current is energized in the diagonal direction of the sheet-like molded body F.
That is, by continuously switching the switches s1 to s4 by the energization control unit 52, the energization direction is switched, and a large amount of current is applied to both ends in the width direction of the sheet-shaped molded body F, so that the sheet-shaped molded body F is uniformly heated. It can be made to.
And by switching an electricity supply pattern continuously in this way, the sheet-like molded object F self-heats with Joule heat, is heated up to about 1300 degreeC, and sintering advances.

  At this time, the control units 37a and 37b adjust the peripheral speeds of the first feeding roll 3a and the second feeding roll 3b, energize the sheet-like molded body F in a state where tensile stress is applied, and advance the sintering. To go. For example, when the peripheral speed of the first power supply roll 3a is V1, the peripheral speed of the second power supply roll 3b is V2, and the contraction rate in the width direction when the sheet-like molded body F is sintered is X%, The peripheral speed V1 of the first power supply roll 3a and the peripheral speed V2 of the second power supply roll 3b are adjusted so as to have a relationship of V1 × (100−X) / 100 <V2 <V1 × 1.1. In this embodiment, since the contraction rate in the width direction of the sheet-like molded body F is 6%, the peripheral speed V1 of the first power supply roll 3a is 100 mm / min, and the peripheral speed V2 of the second power supply roll 3b is 95 mm. / Min. Further, the voltage between the first power supply roll 3a and the second power supply roll 3b is set to 12V, and the current is set to 300A.

  In this way, by conducting current sintering on the sheet-like molded body F, titanium powders located in the skeleton portion of the three-dimensional network structure are firmly bonded to each other, and a porous titanium sintered body is manufactured. In addition, the thickness of the obtained porous titanium foam is 1 mm.

  As described above, according to the metal sintered body manufacturing apparatus 1 of the present invention, electricity is supplied to the sheet-shaped molded body F via the first power supply roll 3a and the second power supply roll 3b, and the sheet-shaped molded body. Since F itself is sintered by self-heating, the sheet-like molded body F can be heated to a high temperature in a short time. In addition, since it is heated to a high temperature in a short time, the time for maintaining it in a high temperature state can be shortened, and even if it is a sheet-like molded body F made of an active metal such as titanium, it reacts with atmospheric gas or the like. Can be suppressed.

  Moreover, since heat is easily diffused at the widthwise end portion of the sheet-like molded body F, the temperature tends to be lower than that at the widthwise central portion. However, in the manufacturing apparatus of the present invention, since the power supply unit 52 and the power supply connection between the both ends of the pair of power supply rolls 3a and 3b are switched, one end of the sheet-shaped molded body F in the width direction is switched. When the end portions of the respective power supply rolls 3a and 3b are connected to each other in parallel with the traveling direction for energization (parallel energization), the end portions of the power supply rolls 3a and 3b are connected to each other diagonally. By switching between energization (diagonal energization), the sheet-shaped molded body F can be uniformly heated by energizing the end portion more than the center portion in the width direction of the sheet-shaped molded body F. Thereby, the temperature difference of the center part and edge part of the sheet-like molded object F can be made small, and the deformation | transformation of the sheet-like molded object F which arises by a temperature difference can be suppressed. In addition, by preventing the deformation of the sheet-like molded body F in this way, it is possible to prevent the occurrence of cracks and the like of the sintered metal body, so that a stable current can flow through the sheet-like molded body F, A uniform metal compact can be obtained.

  Further, the peripheral speeds of the first power supply roll 3a and the second power supply roll 3b are adjusted according to the shrinkage rate of the sheet-shaped molded body F, and the sintering proceeds in a state where tensile stress is applied to the sheet-shaped molded body F. It is possible to correct the deformation of the sheet-like molded body F accompanying the sintering and prevent the occurrence of troubles due to the deformation. Moreover, the tensile stress more than necessary does not act on the sheet-shaped molded body F, and the occurrence of breakage or the like of the sheet-shaped molded body F can be prevented.

Further, since the water-cooled pipe 33 is provided inside the first power supply roll 3a and the second power supply roll 3b, the first power supply roll 3a and the second power supply roll 3b can be prevented from being maintained at a high temperature, and these power supply Roll deterioration can be prevented.
Furthermore, since the first power supply roll 3a, the second power supply roll 3b, the first pressure roll 4a, and the second pressure roll 4b are made of a material having a low coefficient of thermal expansion such as a tungsten alloy, deformation due to heat is suppressed. And can be sintered satisfactorily. And these 1st electric power supply roll 3a, the 2nd electric power supply roll 3b, the 1st press roll 4a, and the 2nd press roll 4b can omit cooling mechanisms, such as cooling piping, by improving heat resistance.

FIG. 6 shows a second embodiment of the present invention. Although 1st Embodiment was comprised with the manufacturing apparatus of the sintered metal body provided with two electric power supply rolls (a 1st electric power supply roll and a 2nd electric power supply roll), 2nd Embodiment is three electric power supply rolls (the 1st electric power supply roll). It is comprised with the manufacturing apparatus of the metal sintered compact provided with the 1 electric power supply roll 103a, the 2nd electric power supply roll 103b, and the 3rd electric power supply roll 103c).
As shown in FIG. 6, both ends of each of the power supply rolls 103a to 103c are connected in parallel to the power supply unit 50 via switches s1 to s6. By switching on and off of these switches s1 to s6 and changing the combination of the ends of the power supply rolls 103a to 103c, the energization direction of the sheet-like molded body F can be switched.
In this case, parallel energization in the direction (c1, c2, c5, c8) in which the widthwise ends of the sheet-like molded body F are connected along the traveling direction of the sheet-like molded body F, and the power supply rolls 103a to 103c are connected. The sheet-shaped molded body F of the sheet-like molded product F is continuously switched between diagonal energization by connecting the ends of the opposing power supply rolls 103a to 103c in the diagonal direction (c3, c4, c6, c7). Control heat generation.

In addition, when the peripheral speed V1 of the first power supply roll 103a, the peripheral speed V2 of the second power supply roll 103b, the peripheral speed V3 of the third power supply roll 103c, and the contraction rate X in the width direction of the sheet-like molded body F, V1 The control units 137a, 137b, and 137c have a relationship of × (100−X) / 100 <V2 <V1 × 1.1 and V2 × (100−X) / 100 <V3 <V2 × 1.1, The peripheral speeds V1, V2, and V3 of the power supply rolls 103a, 103b, and 103c can be set.
Other configurations are the same as those of the first embodiment, and the same reference numerals are given to common portions, and descriptions thereof are omitted.

In addition, this invention is not limited to the said embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.
For example, although it demonstrated as what produces a slurry in the above-mentioned embodiment, the mixing | blending of this slurry, the particle size of a powder, etc. are not limited to this embodiment, The raw material of another mixing | blending and a particle size is used. A slurry may be prepared.
Moreover, the thickness and width of the metal sintered body to be manufactured are not limited to the present embodiment, and other sizes of metal sintered bodies may be manufactured.
Furthermore, although the description has been made with respect to a sintered metal body made of titanium, the present invention is not limited to this, and other sintered metal bodies such as stainless steel and Ni-based alloys may be targeted.
Moreover, although the power supply mechanism has been described as a DC power supply, the power supply mechanism is not limited to this, and an AC power supply or a pulse power supply may be used.

Moreover, in the above-described embodiment, as the energization pattern between the power supply rolls, the energization pattern connecting one end of each power supply roll is described, but one end of one power supply roll and the other It is good also as an electricity supply pattern which connects the both ends of an electric power feeding roll simultaneously.
For example, in the first embodiment, when both ends of the first power supply roll 3a are connected (both switches s1 and s2 are “ON”) and one end of the second power supply roll 3b is connected (for example, the switch s3 is “ON”). ”, The switch s4 is“ OFF ”), and the energization pattern in which the directions c1 and c3 are energized at the same time can be obtained.

  Moreover, although the power supply roll and the pressing roll have been described as being made of a material having a low coefficient of thermal expansion, such as a tungsten alloy, other materials may be used. For example, power supply can be performed efficiently by configuring the first power supply roll and the second power supply roll with a material having excellent conductivity such as copper. In the case of copper, since the thermal expansion coefficient is relatively large, it is necessary to cool sufficiently in order to suppress thermal deformation. Further, the pressing roll may be a ceramic roll.

Moreover, although the 1st press roll and the 2nd press roll were demonstrated as a follower roll, it is not limited to this, The control part which controls the peripheral speed of these press rolls independently in synchronization with each electric power feeding roll It is good also as a thing provided.
Furthermore, although it demonstrated by the structure which has arrange | positioned the electric power roll on the lower side and arrange | positioned the press roll on the upper side, it is not limited to this, arrange | positions the electric power roll on the upper side, arranges the press roll on the lower side. Also good. One of the first power supply roll and the second power supply roll may be arranged on the upper side, and the other may be arranged on the lower side.

DESCRIPTION OF SYMBOLS 1 Manufacturing apparatus of a metal sintered body 2 Sintering chamber 2a Carry-in port 2b Carry-out port 3a, 103a 1st feed roll 3b, 103b 2nd feed roll 4a 1st press roll 4b 2nd press roll 5 Feed mechanism 8 Pressure adjustment mechanism 21 Viewing window 22 Radiation thermometer 32 Power supply connector 33, 43 Water cooling pipe 34, 44 Cooling water supply part 34a Supply pipe 34b Discharge pipe 35 Drive motor 36 Insulating member 37a, 37b, 137a, 137b, 137c Control part 40 Support arm 41 Insulator 42 Load Cell 50 Power Supply Unit 51 Electrode 52 Energization Control Unit 90 Sheet Forming Machine 91 Conveying Roller 92 Carrier Sheet 93 Slurry Storage Unit 94 Doctor Blade 95 Foaming Tank 96 Drying Chamber 103c Third Power Supply Roll

Claims (5)

  An apparatus for manufacturing a sintered metal body that is energized and sintered by self-heating with respect to a sheet-like molded body made of metal powder, and travels the sheet-like molded body and is spaced in the running direction of the sheet-like molded body At least a pair of power supply rolls disposed at a distance, a power supply mechanism for supplying a current to the sheet-like molded body via the pair of power supply rolls, and the sheet-shaped molding disposed to face the pair of power supply rolls And a pair of power supply rolls, both ends of each of the power supply rolls being connected in parallel to the power supply unit of the power supply mechanism, In the mechanism, there is an energization control unit that switches energization connection between the power supply unit and both ends of the power supply roll, and energizes more in the width direction end portion than in the width direction center portion of the sheet-like molded body. Apparatus for producing metal sintered body characterized by being kicked.   The apparatus for manufacturing a metal sintered body according to claim 1, further comprising a control mechanism for independently controlling the peripheral speeds of the pair of power supply rolls.   The metal sintered body according to claim 1 or 2, wherein a cooling pipe is formed inside the power supply roll and the pressing roll, and a cooling mechanism is provided for cooling by circulating a refrigerant in the cooling pipe. Body manufacturing equipment.   The manufacturing method of the metal sintered compact which sinters a sheet-like molded object using the manufacturing apparatus of the metal sintered compact as described in any one of Claim 1 to 3. Manufacture of a metal sintered body that travels a sheet-like molded body made of metal powder and that is sintered by self-heating by energizing the sheet-like molded body between a pair of power supply rolls arranged at intervals in the running direction. A method,
Parallel energization that connects between both ends of the pair of power supply rolls along the running direction of the sheet-like molded body and energizes the widthwise ends of the sheet-like molded body, and both ends of the pair of power supply rolls A method for producing a metal sintered body that energizes the sheet-like formed body while switching between diagonal energizations connected to each other in a diagonal direction.

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