JP2010261073A - Method for manufacturing metal-sintered body and energization sintering apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a metal-sintered body, which can efficiently manufacture the metal-sintered body of high quality at a low cost, and to provide an energization sintering apparatus which is suitable for the method for manufacturing the metal-sintered body. <P>SOLUTION: The energization sintering apparatus 10 includes: a sintering chamber 11 which is provided with a charging port 12 and a delivery port 13; at least a pair of power-feeding rolls 20 and 30 which are arranged in the sintering chamber 11, transport a sheet-like molded body and also feed electricity to the sheet-like molded body; and a power-feeding mechanism 14 which feeds the electricity to the sheet-like molded body through the pair of the power-feeding rolls 20 and 30. The sintering method includes: using the energization sintering apparatus 10; adjusting peripheral speeds of the power-feeding roll 20 arranged in the charging port 12 side and the power-feeding roll 30 arranged in the delivery port 13 side according to the shrinkage of the sheet-like molded body in the travelling direction due to sintering; and feeding the electricity to the sheet-like molded body through the pair of the power-feeding rolls 20 and 30 in such a state of exerting a tensile strength on the sheet-like molded body to make the sheet-like molded body cause self-heating. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a method for manufacturing a metal sintered body made of titanium, stainless steel, a Ni-based alloy, and the like, and an electric current sintering apparatus suitable for the method for manufacturing the metal sintered body.

  As a method for producing the above-mentioned metal sintered body, as described in Patent Document 1, for example, a method is known in which a molded body obtained by mechanically compacting metal powder is heat-sintered. Moreover, as described in Patent Document 2, an organic binder, a plasticizer, water, a surfactant, and the like are mixed with metal powder to form a slurry, and the slurry is molded to form a molded body. The one which heat-sinters is proposed.

In the sintering process of sintering compacted compacts and compacted compacts, the compact is placed in a sintering furnace in a vacuum or reducing atmosphere and heated in the sintering furnace. Alternatively, the burner is heated to raise the atmospheric temperature of the sintering furnace, and the compact is heated and sintered. In particular, when an active metal that easily oxidizes, such as Ti or Cr, is contained, it is necessary to reliably control the atmosphere.
Moreover, in order to perform sintering efficiently, Patent Document 3 proposes a method in which a compact is run and continuously sintered in a high-temperature sintering furnace.

JP-A-62-080201 JP 2007-046089 A JP 09-291302 A

By the way, as mentioned above, when the heater is heated or burner heated in the sintering furnace to increase the ambient temperature, and the molded body charged in the sintering furnace is heated and sintered, the entire sintering furnace is used. Would be heated, resulting in poor thermal efficiency and a significant increase in energy costs required for sintering.
In addition, in order to heat the molded body itself to a predetermined temperature, it is necessary to keep it at a high temperature for a relatively long time. Particularly, in the case of a molded body containing an active metal such as Ti or Cr, the molded body is There was a risk of reacting with the holding gas or the like in contact with the atmospheric gas or the molded body. Furthermore, there is a problem that the sintering process becomes rate-determining and the metal sintered body cannot be produced efficiently.

  The present invention has been made in view of the above-described circumstances, and is a method for producing a metal sintered body capable of producing a high-quality metal sintered body efficiently and at low cost, and the metal sintering. An object of the present invention is to provide an electric current sintering apparatus suitable for a method for manufacturing a body.

  In order to solve such problems and achieve the above-mentioned object, the method for producing a metal sintered body according to the present invention includes a sheet-like metal that is heated and sintered while a sheet-like molded body made of metal powder is run. A method for producing a sintered metal body for producing a sintered body, comprising: an inlet for charging the sheet-like formed body; and a sintering chamber provided with an outlet for producing the sintered metal body; At least a pair of power supply rolls arranged at the inlet side and the outlet for manufacturing in the sintering chamber, for running the sheet-shaped molded body and supplying electricity to the sheet-shaped molded body, and the pair of power supply rolls And a feeding mechanism for supplying electricity to the sheet-shaped molded body, and using the current sintering apparatus, the inlet side according to contraction in the running direction accompanying the sintering of the sheet-shaped molded body The power supply roll disposed on the outlet side The sheet shape is adjusted by energizing the sheet-shaped molded body through the pair of power supply rolls in a state in which the peripheral speed with the arranged power feeding roll is adjusted and tensile stress is applied to the sheet-shaped molded body. It is characterized in that the compact is sintered by self-heating.

  In the method for producing a metal sintered body of the present invention configured as described above, when the sheet-like molded body made of metal powder is sintered, the inlet into which the sheet-like molded body is charged and the metal A sintering chamber provided with a production outlet for producing a sintered body, and disposed in the inlet and the outlet in the sintering chamber to run the sheet-like molded body and to the sheet-like molded body Using a current-carrying apparatus comprising at least a pair of power supply rolls for supplying electricity and a power supply mechanism for supplying electricity to the sheet-like molded body through the pair of power supply rolls, And the sheet-like molded body itself is self-heated by supplying electricity to the sheet-like molded body via a pair of power supply rolls arranged at the outlet, so that the sheet-shaped molded body can be quickly Up to high temperature It is possible to heat.

  In other words, since the sheet-like molded body itself, which is the heating target, can be heated, the thermal efficiency is dramatically improved and the energy cost is greatly reduced as compared with the conventional sintering method using a sintering furnace. Can do. In addition, since it is heated to a high temperature in a short time, it is possible to suppress the reaction of the sheet-shaped molded body with the atmospheric gas etc. by shortening the time for maintaining it in a high temperature state. It becomes possible to produce. Furthermore, since sintering can be performed in a short time and the sheet-like molded body can be sintered while traveling, the sheet-like molded body can be continuously sintered, and the production efficiency of the metal sintered body can be increased. Can be greatly improved.

Further, the sheet-like molded body shrinks in the width direction, the running direction, and the thickness direction as the sintering proceeds. Moreover, since heat is easily dissipated at the widthwise end of the sheet-like molded body, the temperature tends to be lower than that at the widthwise center. For this reason, the shrinkage rate of the width direction edge part is small, and the shrinkage rate of the width direction center part becomes large, and it deform | transforms so that the width direction edge part of a sheet-like molded object may wave. When such a deformation | transformation generate | occur | produces, there exists a possibility that a crack may arise in a metal sintered compact or a feed roll may be damaged.
Therefore, in the present invention, in response to the shrinkage in the running direction accompanying the sintering of the sheet-shaped molded body, a power supply roll disposed on the inlet side of the sintering chamber, and a power supply roll disposed on the outlet side A configuration is adopted in which the sheet-shaped molded body is energized via the pair of power supply rolls in a state where the peripheral speed is adjusted and tensile stress is applied to the sheet-shaped molded body. In this way, by conducting current sintering while applying tensile stress, it is possible to correct the deformation of the sheet-like molded body accompanying the progress of the sintering, and to prevent the occurrence of troubles due to the aforementioned deformation in advance. be able to.
The method for producing a metal sintered body of the present invention is particularly suitable for producing a sheet-like metal sintered body having a plate thickness of 30 μm to 3 mm, preferably 50 μm to 500 μm. . In addition, as the plate thickness of the molded body becomes thinner, the ratio of the heat capacity of the furnace body and the jig to the molded body to be sintered increases, and the energy efficiency per unit weight or unit volume decreases. Moreover, when a molded object is too thin, conveyance by an electric power feeding roll will become difficult.

  Here, the circumferential speed of the power supply roll disposed on the inlet side is set to V1, the peripheral speed of the power supply roll disposed on the outlet side is set to V2, and the width direction when the sheet-like molded body is sintered is set. When the shrinkage rate of X is X%, the peripheral speed V1 of the power supply roll arranged on the charging inlet side so as to have a relationship of V1 × (100−X) / 100 <V2 <V1 × 1.1, It is preferable to adjust the peripheral speed V2 of the power supply roll arranged on the outlet side.

  In this case, the peripheral speed V2 of the power supply roll disposed on the outlet side is V2 with respect to the shrinkage ratio X in the width direction of the sheet-like molded body and the peripheral speed V1 of the power supply roll disposed on the loading inlet side. Since it is adjusted to be> V1 × (100−X) / 100, it is possible to perform sintering in a state in which a tensile stress is applied to the sheet-like molded body without fail. In addition, since the peripheral speed V2 of the power feeding roll arranged on the outlet side is V2 <V1 × 1.1, the sheet-like molded body is not subjected to unnecessary tensile stress, and the sheet-like roll It becomes possible to prevent the molded body from being broken and the like, and a high-quality sintered metal body can be produced.

Further, before conducting the electric current sintering using the electric current sintering device, the electric resistance value P of the sheet-like molded body is 10 × 10 ⁻⁶ Ω · m ≦ P ≦ 1500 × 10 ⁻⁶ Ω · m. It is preferable to adjust within the range.
In the electric current sintering apparatus, since it is configured to self-heat the sheet-like molded body by energizing through a power supply roll, in order to promote moderate conductivity for energization and generation of Joule heat A moderate electrical resistance is required. Therefore, by adjusting the electric resistance value P of the sheet-like molded body within the range of 10 × 10 ⁻⁶ Ω · m ≦ P ≦ 1500 × 10 ⁻⁶ Ω · m, it is possible to reliably energize through the power supply roll. And can be heated to a high temperature by self-heating. In order to achieve the above-described effect with certainty, it is preferable to adjust the electric resistance value P within a range of 30 × 10 ⁻⁶ Ω · m ≦ P ≦ 500 × 10 ⁻⁶ Ω · m.

  The electric current sintering apparatus of the present invention is an electric current sintering apparatus for energizing and sintering a sheet-shaped molded body made of metal powder by self-heating, and an inlet into which the sheet-shaped molded body is inserted; A sintering chamber provided with a production outlet from which the metal sintered body is produced, and the sheet-like molded body that is disposed on the inlet side and the production outlet in the sintering chamber and travels the sheet-like molded body. An electric power supply roll disposed on the side of the loading port, and at least a pair of electric power supply rolls for supplying electricity to the sheet-like molded body through the pair of electric power supply rolls. It is characterized by including a control mechanism for independently controlling the peripheral speed and the peripheral speed of the power supply roll disposed on the outlet side.

  According to the electric current sintering apparatus of this configuration, at least a pair of power supply rolls that run the sheet-shaped molded body and supply electricity to the sheet-shaped molded body, and a peripheral speed of the power supply roll on the inlet side , And a control mechanism for independently controlling the peripheral speed of the power supply roll on the outlet side, and according to the shrinkage in the running direction accompanying the sintering of the sheet-like molded body, It becomes possible to adjust the peripheral speed between the power supply roll disposed on the outlet side and the power supply roll disposed on the inlet side, and in the state where tensile stress is applied to the sheet-like molded body, The sheet-shaped molded body can be energized and sintered through a power supply roll. Therefore, it is possible to suppress deformation of the sheet-like molded body accompanying the progress of sintering, and it is possible to efficiently produce a high-quality metal sintered body.

Here, it is preferable that a cooling path is formed inside the power supply roll, and a cooling mechanism is provided that cools the power supply roll by circulating a refrigerant in the power supply roll.
In this case, when the sheet-shaped molded body self-heats, the power supply roll in contact with the sheet-shaped molded body also becomes high temperature. Thus, by providing a cooling mechanism in the power supply roll, early deterioration of the power supply roll can be prevented.

Moreover, it is preferable to have a pressure roll that clamps the traveling sheet-like molded body together with the power supply roll, and to have a pressure adjustment mechanism that adjusts the clamping pressure between the pressure roll and the power supply roll.
In this case, by adjusting the clamping pressure between the holding roll and the power supply roll, the sheet-like molded body can be reliably supported and conveyed, and a stable current can be made to contact the power supply roll reliably. And a uniform sintered body can be obtained.

  According to the present invention, a method of manufacturing a metal sintered body capable of producing a high-quality metal sintered body efficiently and at low cost, and an electric current sintering apparatus suitable for the method of manufacturing the metal sintered body Can be provided.

It is a flowchart which shows the manufacturing method of the metal sintered compact which is the 1st Embodiment of this invention. In the manufacturing method of the metal sintered compact shown in FIG. 2, it is a schematic explanatory drawing of the sheet forming machine which shape | molds a sheet-like molded object. It is explanatory drawing which shows the outline | summary of the electric current sintering apparatus which is 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 electric sintering apparatus shown in FIG. It is explanatory drawing of the support structure of the electric power feeding roll of the electric sintering apparatus shown in FIG.3 and FIG.4. It is a flowchart which shows the manufacturing method of the metal sintered compact which is the 2nd Embodiment of this invention. It is a flowchart which shows the manufacturing method of the metal sintered compact which is the 3rd Embodiment of this invention. It is a flowchart which shows the manufacturing method of the metal sintered compact which is the 4th Embodiment of this invention. In the manufacturing method of the metal sintered compact shown in FIG. 8, it is a schematic explanatory drawing of the powder rolling machine which shape | molds a sheet-like molded object. It is explanatory drawing which shows the outline | summary of the electric current sintering apparatus which is other embodiment of this invention.

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 5 show a method for producing a metal sintered body and a current sintering apparatus used for the method for producing the metal sintered body according to the first embodiment of the present invention.
The method for producing a metal sintered body according to the present embodiment produces a sintered body of porous titanium used as, for example, a filter.

  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 effervescent slurry S is prepared by mixing an organic binder, a foaming agent, a plasticizer, water and, if necessary, a surfactant with titanium powder, titanium hydride powder, or a mixed powder thereof. To do.
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. used.

Water-soluble methylcellulose or polyvinyl alcohol was used as an organic binder to which the above mixed powder was bound. Neopentane, hexane and peptane were used as blowing agents. Glycerin was used as a plasticizer. Alkylbenzene sulfonate was used as the 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, plasticizer: 0.1 to 15% by mass, surfactant. A slurry S was prepared by mixing at a ratio of 0.05 to 5% by mass and water: the balance.

  Next, a foamable sheet-like molded body F is formed from the slurry S. Here, the molding step S2 and the foaming step S3 are performed using a sheet molding machine 80 shown in FIG. The sheet forming machine 80 includes a carrier sheet 82 driven by a conveyance roller 81, a slurry storage unit 83 in which the slurry S is stored, a doctor blade 84 disposed on the carrier sheet 82, a foaming tank 85, And a drying chamber 86.

(Molding step S2)
In the molding step S2, the slurry S is supplied from the slurry reservoir 83 onto the carrier sheet 82 using the sheet molding machine 80 shown in FIG. 2, and the thickness of the slurry S on the carrier sheet 82 is set to a predetermined value by the doctor blade 84. To produce a sheet-like 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 charged into the foaming tank 85 together with the carrier sheet 82, held at a temperature of 70 ° C. and a humidity of 90% for 1 hour, and warm air of 80 ° C. is blown in the drying chamber 86 for 1 hour. And dry with warm air. By the foaming step S3, the foaming agent in the sheet-like slurry is foamed to produce a foamed molded article having a three-dimensional network structure and titanium powder positioned in the skeleton portion of the network structure.

(Degreasing step S4)
The aforementioned foamed molded article is separated from the carrier sheet 82 and placed on a support plate made of zirconia, inserted into 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 to each other with a certain strength. It becomes possible.

(Electrical sintering process S7)
The sheet-like molded body F separated from the support plate is subjected to current sintering using the current sintering apparatus 10 shown in FIGS. Specifically, electricity is supplied to the sheet-shaped molded body F, the sheet-shaped molded body F is self-heated by Joule heat, and is held at 1300 ° C. for 1 to 5 minutes in an Ar gas atmosphere.

Next, the electric current sintering apparatus 10 used in the electric current sintering step S7 will be described with reference to FIGS.
As shown in FIG. 3, the electric current sintering apparatus 10 includes a sintering chamber 11 having an inlet 12 and an outlet 13, and a first power supply roll 20 disposed on the inlet 12 side in the sintering chamber 11. A first pressing roll 40 disposed opposite to the upper portion of the first power supply roll 20, a second power supply roll 30 disposed on the outlet 13 side in the sintering chamber 11, and the second power supply roll 30. A second presser roll 50 disposed opposite to the upper part, and a power supply mechanism 14 that supplies electricity to the sheet-like molded body F via the first power supply roll 20 and the second power supply roll 30 are provided.

As shown in FIGS. 4 and 5, the first power supply roll 20 and the second power supply roll 30 are extended in a direction orthogonal to the traveling direction of the sheet-like molded body F, and one side thereof (FIG. 4 and FIG. 5, the end on the left side is pivotally supported on the inner wall portion of the sintering chamber 11 via the insulating plates 21 and 31, and the other side (right side in FIG. 4 and FIG. 5) is the portion of the sintering chamber 11. It is projected outside.
Of the first power supply roll 20 and the second power supply roll 30, power supply connectors 22 and 32 that supply electricity from the power supply mechanism 14, the first power supply roll 20, and the second power supply part are projected to the outside from the sintering chamber 11. The cooling water supply units 24 and 34 for supplying cooling water to the water cooling pipes 23 and 33 provided inside the power supply roll 30, the insulating members 28 and 38, and the first power supply roll 20 and the second power supply roll 30 are rotated. Drive motors 29 and 39 for driving are provided.

  Here, as shown in FIG. 5, the first power supply roll 20 and the second power supply roll 30 have a double pipe structure in which water-cooled pipes 23 and 33 are disposed. The cooling water supply units 24 and 34 are provided with supply pipes 25 and 35 and discharge pipes 26 and 36, and cooling water is supplied from the supply pipes 25 and 35 to the water cooling pipes 23 and 33. Cooling water supplied toward one side (the left side in FIGS. 4 and 5) of the first power supply roll 20 and the second power supply roll 30 through the water cooling pipes 23 and 33 passes through the annular space outside the water cooling pipes 23 and 33. The first power supply roll 20 and the second power supply roll 30 are distributed toward the other end side (the right side in FIGS. 4 and 5) and discharged to the outside through the discharge pipes 26 and 36.

The power feeding connectors 22 and 32 are cylindrical members provided on the outer peripheral surfaces of the rotating first power feeding roll 20 and the second power feeding roll 30, and the power feeding mechanism 14 is connected to the power feeding connectors 22 and 32 via the electrode 15. It is set as the structure where electricity is supplied from. In the present embodiment, the power feeding mechanism 14 is a DC power source.
The insulating members 28 and 38 are provided to prevent energization between the drive motors 29 and 39 that rotationally drive the first power supply roll 20 and the second power supply roll 30 and the power supply connectors 22 and 32. In the embodiment, the coupling is made of insulating resin.

As shown in FIGS. 3 and 4, the first pressing roll 40 and the second pressing roll 50 are pivotally supported by a pair of pivoting arms 41 and 51 arranged so as to penetrate the ceiling portion of the sintering chamber 11. It is supposed to be configured. It should be noted that insulators 42 and 52 are interposed in the shaft support arms 41 and 51.
The pair of pivot arms 41 and 51 are supported by support portions 43 and 53 extending in parallel with the extending direction of the first pressing roll 40 and the second pressing roll 50. Further, the support portions 43 and 53 are supported by lifting devices 44 and 54 installed on the upper portion of the ceiling portion of the sintering chamber 11, and adjust the vertical positions of the first pressing roll 40 and the second pressing roll 50. The lifting devices 44 and 54 adjust the clamping pressure between the first feeding roll 20 and the first pressing roll 40 and the clamping pressure between the second feeding roll 30 and the second pressing roll 50. It is set as the structure.
In addition, the first pressing roll 40 and the second pressing roll 50 have a double-pipe structure in which water-cooled pipes are arranged inside, similar to the first feeding roll 20 and the second feeding roll 30 described above. The cooling water is circulated by a cooling water supply means (not shown).

Moreover, the installation interval of the 1st press roll 40 and the 2nd press roll 50, and the installation interval of the 1st power supply roll 20 and the 2nd power supply roll 30 are 100 mm in this embodiment. The roll interval is determined in consideration of the heating time required for the product (depending on the material and application) and the production rate.
Furthermore, the first power supply roll 20, the second power supply roll 30, the first pressure roll 40, and the second pressure roll 50 are made of a material having a small coefficient of thermal expansion, such as a tungsten alloy.

  And as shown in FIG. 3, the 1st electric power feeding roll 20, the 2nd electric power feeding roll 30, the 1st press roll 40, and the 2nd press roll 50 are the control parts (1st electric power feeding) which controls each peripheral speed independently. A roll control unit 61, a second feeding roll control unit 62, a first pressing roll control unit 63, and a second pressing roll control unit 64).

  When the sheet-shaped formed body F is subjected to current-sintering using such an electric current sintering apparatus 10, first, the sheet-shaped formed body F is sandwiched between the first power supply roll 20 and the first pressing roll 40. The sheet-like molded product F is sandwiched between the second feeding roll 30 and the second pressing roll 50 and the first feeding roll 20, the first pressing roll 40, the second feeding roll 30 and the second pressing roll 50 are rotationally driven. Transport. At this time, the sheet-shaped molded body F is energized from the power supply mechanism 14 via the first power supply roll 20 and the second power supply roll 30. Then, the sheet-like molded body F is self-heated by Joule heat, is heated to about 1300 ° C., and sintering proceeds.

At this time, the peripheral speed between the first power supply roll 20 and the second power supply roll 30 is adjusted by the first power supply roll control unit 61 and the second power supply roll control unit 62, and a tensile stress is applied to the sheet-like molded body F. In this state, power is applied and sintering proceeds.
Here, when the peripheral speed of the first power supply roll 20 is V1, the peripheral speed of the second power supply roll 30 is V2, and the contraction rate in the width direction when the sheet-like molded body F is sintered is X%. , V1 × (100−X) / 100 <V2 <V1 × 1.1 The circumferential speed V1 of the first power supply roll 20 and the peripheral speed V2 of the second power supply roll 30 are adjusted.

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 20 is 100 mm / min, and the peripheral speed V2 of the second power supply roll 30 is 95 mm. / Min.
Further, the voltage between the first power supply roll 20 and the second power supply roll 30 is set to 12V, and the current is set to 300A.
In this way, by performing 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 produced. In addition, the thickness of the obtained porous titanium sintered compact is 1 mm.

According to the method for producing a metal sintered body (porous titanium sintered body) and the electric current sintering apparatus 10 according to the first embodiment of the present invention having such a configuration, the first power supply roll 20 and the second Since electricity is supplied to the sheet-like molded body F via the power supply roll 30 and the sheet-like molded body F itself is sintered by self-heating, the sheet-like molded body F can be removed in a short time. It can be heated to high temperatures. Therefore, compared with the sintering method using the conventional sintering furnace, the thermal efficiency is dramatically improved and the energy cost can be greatly reduced.
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. Therefore, a high-quality metal sintered body (porous titanium sintered body) can be produced.

  Furthermore, in this embodiment, when the circumferential speed V1 of the first power supply roll 20 and the peripheral speed V2 of the second power supply roll 30 are X% as the shrinkage rate in the width direction when the sheet-like molded body F is sintered. , V1 × (100−X) / 100 <V2 <V1 × 1.1 is controlled, and specifically, with respect to the shrinkage rate 6% in the width direction of the sheet-like molded body F. Since the peripheral speed V1 of the first power supply roll 20 is set to 100 mm / min and the peripheral speed V2 of the second power supply roll 30 is set to 95 mm / min, an appropriate tensile stress is applied to the sheet-like molded body F. Sintering can be advanced in a state, and the deformation | transformation of the sheet-like molded object F accompanying progress of sintering can be corrected, and generation | occurrence | production of the trouble resulting from this deformation | transformation can be prevented beforehand. 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.

Moreover, in this embodiment, since the slurry S which mixed the organic binder, the foaming agent, the plasticizer, water, and the surfactant as needed in the titanium powder, the titanium hydride powder, or these mixed powders is used. The conductivity is not ensured simply by molding. Therefore, the sheet-like slurry is heated from 800 ° C. to 1000 ° C. in the pre-sintering furnace and pre-sintered to bind titanium powders located in the skeleton part of the three-dimensional network structure to have a conductive sheet shape. Since the molded body F is produced, it becomes possible to energize the sheet-shaped molded body F by the energization heating device 10 thereafter. That is, by the pre-sintering step, the electrical resistance value P of the sheet-like molded body F is set in the range of 20 × 10 ⁻⁶ Ω · m ≦ P ≦ 1500 × 10 ⁻⁶ Ω · m, more specifically 100 ×. By adjusting to 10 ⁻⁶ Ω · m, adequate conductivity for energization and electrical resistance for promoting the generation of Joule heat are ensured.

  Moreover, in the electric sintering apparatus 10 which is this embodiment, the 1st electric power supply roll 20, the 2nd electric power supply roll 30, the 1st press roll 40, and the 2nd press roll 50 control each peripheral speed independently. Since the control part (the 1st electric power feeding roll control part 61, the 2nd electric power feeding roll control part 62, the 1st press roll control part 63, the 2nd press roll control part 64) is provided, the contraction rate of the sheet-like molded object F is obtained. Accordingly, the peripheral speeds of the first power supply roll 20 and the second power supply roll 30 can be controlled.

  Furthermore, the 1st press roll 40 and the 2nd press roll 50 are provided, and the height position of these 1st press roll 40 and the 2nd press roll 50 is set as the structure which can be adjusted with the raising / lowering apparatus 44,54. Therefore, it becomes possible to adjust the clamping pressure by the 1st press roll 40, the 1st electric power feeding roll 20, the 2nd press roll 50, and the 2nd electric power feeding roll 30, and support and convey the sheet-like molded object F reliably. In addition, the first power supply roll 20 and the second power supply roll 30 can be reliably brought into contact with each other and subjected to current sintering. Therefore, the sheet-like molded body F can be reliably brought into contact with the first power supply roll 20 and the second power supply roll 30 to flow a stable current, and a uniform metal sintered body can be obtained.

  Further, the water cooling pipes 23 and 33 are disposed inside the first power supply roll 20 and the second power supply roll 30, and the cooling water supply parts 24 and 34 for circulating the cooling water through the water cooling pipes 23 and 33 are provided. The first power supply roll 20 and the second power supply roll 30 can be prevented from being maintained in a high temperature state, and early deterioration of the first power supply roll 20 and the second power supply roll 30 can be prevented. Moreover, since the cooling mechanism which distribute | circulates cooling water is also arrange | positioned inside the 1st press roll 40 and the 2nd press roll 50, these 1st press roll 40 and the 2nd press roll 50 also deteriorate early. Can be prevented.

  Furthermore, in this embodiment, since the 1st electric power supply roll 20, the 2nd electric power supply roll 30, the 1st press roll 40, and the 2nd press roll 50 are comprised with the materials with small thermal expansion coefficients, such as a tungsten alloy, self Even if the temperature of the first power supply roll 20, the second power supply roll 30, the first presser roll 40, and the second presser roll 50 brought into contact with the heated sheet-like molded body F rises, the first power supply roll 20 The deformation of the second feeding roll 30, the first pressing roll 40, and the second pressing roll 50 can be suppressed, and the current sintering can be performed satisfactorily.

  Next, as a method for manufacturing a metal sintered body according to the second embodiment of the present invention, a method for manufacturing a dense sheet-like titanium sintered body using the above-described current sintering apparatus is shown in the flow chart of FIG. This will be described with reference to the drawings.

(Slurry production process S11)
In the slurry production step S11, an organic binder, a plasticizer, water and, if necessary, an antifoaming agent such as alcohol are mixed with titanium powder, titanium hydride powder, or a mixed powder thereof to produce a slurry S.
In this embodiment, a mixed powder of titanium hydride powder having an average particle diameter of 5 to 15 μm and pure titanium powder having an average particle diameter of 5 to 15 μm obtained by dehydrogenating the titanium hydride powder is used as a raw material powder. used.

Water-soluble methylcellulose or polyvinyl alcohol was used as an organic binder to which the above mixed powder was bound. Glycerin was used as a plasticizer.
These raw materials were mixed at a ratio of mixed powder: 5 to 80% by mass, organic binder: 0.05 to 10% by mass, plasticizer: 10 to 40% by mass, and water: remainder to prepare slurry S. .

(Molding step S12)
In the forming step S12, the slurry S was applied onto the carrier sheet by an application device equipped with a doctor blade, and a sheet-like slurry having a width of 110 mm, a length of 200 mm, and a thickness of 0.07 mm was formed.

(Degreasing step S14)
The sheet-like slurry is separated from the carrier sheet and placed on a support plate made of zirconia, inserted into a degreasing furnace, and kept at 550 ° C. for 5 hours in a vacuum atmosphere of 5 × 10 ⁻² Pa. Is done. Thereby, the fat (organic binder etc.) contained in the sheet-like slurry is volatilized and removed. In the sheet-like slurry in this state, the titanium powders are not bonded to each other and have no electrical conductivity. In addition, reaction between titanium in the sheet slurry and the support plate is prevented by using a support plate made of zirconia.

(Pre-sintering step S15)
The degreased sheet-like slurry is charged into the pre-sintering furnace together with the support plate. In the pre-sintering furnace, the degreased sheet-like slurry is held at 800 to 1000 ° C. for 1 to 30 minutes in a vacuum atmosphere of 5 × 10 ⁻³ Pa. Thereby, the sheet-like molded object F which has electroconductivity is produced when titanium powder couple | bonds together. Here, the electrical resistance value P of the sheet-like molded body F is adjusted within the range of 10 × 10 ⁻⁶ Ω · m ≦ P ≦ 1000 × 10 ⁻⁶ Ω · m. In the present embodiment, P = 200 × It is set to 10 ⁻⁶ Ω · m.

(Cutting step S16)
In the cutting step S16, the width end portion of the sheet-like molded body F produced by being heated and sintered 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 to each other with a certain strength. It becomes possible.

(Electrical sintering step S17)
The sheet-like molded body F separated from the support plate is subjected to current sintering using the current sintering apparatus shown in FIGS. Specifically, electricity is supplied to the sheet-shaped molded body F, the sheet-shaped molded body F is heated by self-heating by Joule heat, and held at 1300 ° C. for 1 to 5 minutes in an Ar gas atmosphere.

At this time, the peripheral speed between the first power supply roll 20 and the second power supply roll 30 is adjusted by the first power supply roll control unit 61 and the second power supply roll control unit 62, and a tensile stress is applied to the sheet-like molded body F. In this state, power is applied and sintering proceeds.
Here, when the peripheral speed of the first power supply roll 20 is V1, the peripheral speed of the second power supply roll 30 is V2, and the contraction rate in the width direction when the sheet-like molded body F is sintered is X%. , V1 × (100−X) / 100 <V2 <V1 × 1.1 The circumferential speed V1 of the first power supply roll 20 and the peripheral speed V2 of the second power supply roll 30 are adjusted.

In the present embodiment, since the contraction rate in the width direction of the sheet-like molded body F is 5%, the peripheral speed V1 of the first power supply roll 20 is 100 mm / min, and the peripheral speed V2 of the second power supply roll 30 is 100 mm. / Min.
Further, the voltage between the first power supply roll 20 and the second power supply roll 30 is set to 28V, and the current is set to 250A.

  In this way, the titanium powders in the sheet-like molded body F are firmly bonded to each other, and a dense sheet-like titanium sintered body (metal sintered body) is produced. The obtained titanium sintered body (metal sintered body) has a thickness of 0.05 mm.

  According to the method of manufacturing a metal sintered body having this configuration, the first power supply roll 20 and the second power supply roll 20 of the current sintering apparatus 10 are selected according to the shrinkage rate (5%) in the width direction of the sheet-like molded body F having a dense structure. Since the circumferential speeds V1 and V2 of the power supply roll 30 are set, and the current sintering is performed in a state where the tensile stress is applied to the sheet-like molded body F, deformation due to the sintering can be suppressed, and a high-quality metal sintered body (Dense sheet-like titanium sintered body) can be produced.

  Next, as a method for manufacturing a metal sintered body according to the third embodiment of the present invention, a method for manufacturing a porous stainless steel sintered body using the above-described current sintering apparatus 10 is described with reference to the flow chart of FIG. This will be described with reference to the drawings.

(Slurry production process S21)
In the slurry preparation process S21, an organic binder, a foaming agent, a plasticizer, water, and a surfactant as necessary are mixed into a water atomized powder of SUS316, which is a kind of stainless steel, to produce a foamable slurry S.
In this embodiment, SUS316 water atomized powder having an average particle size of 10 to 20 μm was used as the raw material powder.

Water-soluble methylcellulose or polyvinyl alcohol was used as an organic binder to which the above mixed powder was bound. Neopentane, hexane and peptane were used as blowing agents. Glycerin was used as a plasticizer. Alkylbenzene sulfonate was used as the surfactant.
Water raw atomized powder: 5 to 80% by mass, organic binder: 0.05 to 10% by mass, foaming agent: 0.05 to 10% by mass, plasticizer: 0.1 to 15% by mass, surface activity A slurry S was prepared by mixing at a ratio of agent: 0.05 to 5% by mass and water: remainder.

(Molding step S22)
In the molding step S22, the slurry S is supplied from the slurry reservoir 83 onto the carrier sheet 82 using the sheet molding machine 80 shown in FIG. 2, and the thickness of the slurry S on the carrier sheet 82 is set to a predetermined value by the doctor blade 84. To produce a sheet-like slurry having a width of 110 mm, a length of 200 mm, and a thickness of 3.5 mm.

(Foaming step S23)
In the foaming step S23, the sheet-like slurry is held together with the carrier sheet 82 at a temperature of 70 ° C. and a humidity of 90% for 1 hour, and warm air at 80 ° C. is blown for 1 hour to dry the air. By the foaming step S23, the foaming agent in the sheet-like slurry is foamed to produce a foamed molded article having a three-dimensional network structure and SUS316 powder positioned on the skeleton portion of the network structure.

(Degreasing step S24)
The aforementioned foamed molded article is separated from the carrier sheet 82 and placed on a support plate made of zirconia, inserted into 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 SUS316 powders are not bonded to each other and have no electrical conductivity. In addition, reaction of SUS316 in a foaming molding and a support plate is prevented by using the support plate made from a zirconia.

(Pre-sintering step S25)
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 SUS316 powder located in the 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 S26)
In the cutting step S26, 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 SUS316 powders are bonded to each other with a constant strength. It becomes possible.

(Electrical sintering step S27)
The sheet-like molded body F separated from the support plate is subjected to current sintering using the current sintering apparatus 10 shown in FIGS. Specifically, electricity is supplied to the sheet-shaped molded body F, the sheet-shaped molded body F is self-heated by Joule heat, and is held at 1200 ° C. for 1 to 5 minutes in an Ar gas atmosphere.
At this time, the first power supply roll control unit 61 and the second power supply roll control unit 62 adjust the peripheral speeds V1 and V2 of the first power supply roll 20 and the second power supply roll 30 to apply tensile stress to the sheet-shaped molded body F. Electricity is applied in the applied state, and sintering proceeds.
Specifically, the peripheral speed of the first power supply roll 20 is V1, the peripheral speed of the second power supply roll 30 is V2, and the contraction rate in the width direction when the sheet-like molded body F is sintered is X%. In this case, the peripheral speed V1 of the first power supply roll 20 and the peripheral speed V2 of the second power supply roll 30 are adjusted so as to have a relationship of V1 × (100−X) / 100 <V2 <V1 × 1.1. .

In the present embodiment, since the shrinkage rate in the width direction of the sheet-like molded body F is 15%, the peripheral speed V1 of the first power supply roll 20 is 100 mm / min, and the peripheral speed V2 of the second power supply roll 30 is 110 mm. / Min.
Further, the voltage between the first power supply roll 20 and the second power supply roll 30 is set to 5V, and the current is set to 680A.

  In this way, the SUS316 powders located in the skeleton portion of the three-dimensional network structure are firmly bonded to each other, and a porous stainless steel sintered body is produced. In addition, the thickness of the obtained porous stainless steel sintered compact is 3 mm.

  According to the method of manufacturing a metal sintered body having this configuration, the first power supply roll 20 and the first power supply roll 20 of the electric current sintering apparatus 10 and the first number are selected in accordance with the shrinkage rate (15%) in the width direction of the sheet-like molded body F having a porous structure. 2 Since the peripheral speeds V1 and V2 of the power supply roll 30 are set and the current sintering is performed in a state where tensile stress is applied to the sheet-like molded body F, deformation due to sintering can be suppressed, and high-quality metal sintering It becomes possible to produce a body (porous stainless steel sintered body).

  Next, as a method for producing a metal sintered body according to the fourth embodiment of the present invention, a method for producing a solid stainless steel sintered body, not porous, using the above-described current sintering apparatus 10 is used. This will be described with reference to the flowchart of FIG.

(Powder rolling process S31)
In the powder rolling step, SUS316 water atomized powder D having an average particle size of 20 to 40 μm was prepared, and as shown in FIG. 9, a pair of rolling rolls 91 and a powder supply hopper 92 arranged to face each other were provided. A sheet-like molded product F is produced using a powder rolling machine 90. Thereby, the sheet-like molded object F of width 30mm, length 200mm, and thickness 0.7mm was shape | molded.
Here, since this sheet-like molded object F is what rolled the powder D which consists of stainless steel, it is equipped with electroconductivity.

(Electric sintering process S37)
The formed sheet-like molded body F is subjected to current sintering using the current sintering apparatus 10 shown in FIGS. Specifically, electricity is supplied to the sheet-shaped molded body F, the sheet-shaped molded body F is self-heated by Joule heat, and is held at 1200 ° C. for 1 to 5 minutes in an Ar gas atmosphere.

At this time, the first power supply roll control unit 61 and the second power supply roll control unit 62 adjust the peripheral speeds V1 and V2 between the first power supply roll 20 and the second power supply roll 30, and tensile stress is applied to the sheet-like molded body F. In this state, electricity is applied and sintering proceeds.
Here, when the peripheral speed of the first power supply roll 20 is V1, the peripheral speed of the second power supply roll 30 is V2, and the contraction rate in the width direction when the sheet-like molded body F is sintered is X%. , V1 × (100−X) / 100 <V2 <V1 × 1.1 The circumferential speed V1 of the first power supply roll 20 and the peripheral speed V2 of the second power supply roll 30 are adjusted.

In the present embodiment, since the contraction rate in the width direction of the sheet-like molded body F is 2%, the peripheral speed V1 of the first power supply roll 20 is 100 mm / min, and the peripheral speed V2 of the second power supply roll 30 is 105 mm. / Min.
Further, the voltage between the first power supply roll 20 and the second power supply roll 30 is set to 12V, and the current is set to 830A.

  In this way, the SUS316 powder in the sheet-shaped molded body F is firmly bonded to each other by conducting current sintering on the sheet-shaped molded body F, and a dense sheet-shaped stainless steel sintered body (metal sintered body). Is produced. In addition, the thickness of the obtained stainless steel sintered compact (metal sintered compact) shall be 0.5 mm.

  According to the method for manufacturing a metal sintered body having this configuration, the first power supply roll 20 and the second power supply roll 20 of the current sintering apparatus 10 are selected according to the shrinkage rate (2%) in the width direction of the sheet-like molded body F having a dense structure. Since the circumferential speeds V1 and V2 of the power supply roll 30 are set, and the current sintering is performed in a state where the tensile stress is applied to the sheet-like molded body F, deformation due to the sintering can be suppressed, and a high-quality metal sintered body (Dense sheet-like stainless steel sintered body) can be produced.

As mentioned above, although embodiment of this invention was described, this invention is not limited to this, It can change suitably in the range which does not deviate from the technical idea of the invention.
For example, although it demonstrated as what produces a slurry in 1st-3rd embodiment, the mixing | blending of this slurry, the particle size of a powder, etc. are not limited to this embodiment, Other mixing | blendings, particle size of A slurry may be produced using raw materials.

Moreover, the thickness and width of the metal sintered body to be produced are not limited to this embodiment, and other sizes of metal sintered bodies may be produced.
Furthermore, although the description has been made with respect to a sintered metal body made of titanium or stainless steel, the present invention is not limited to this, and another sintered metal body such as a Ni-based alloy may be targeted.
Further, although the power supply mechanism has been described as a DC power supply, the power supply mechanism is not limited to this, and may be an AC power supply or a pulse power supply.

  Moreover, although demonstrated as what comprised the 1st electric power feeding roll, the 2nd electric power feeding roll, the 1st press roll, and the 2nd press roll with the material with small thermal expansion coefficients, such as a tungsten alloy, another material may be sufficient. . 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.

  Furthermore, although it demonstrated as an electric current sintering apparatus provided with two power supply rolls (a 1st power supply roll and a 2nd power supply roll), it is not limited to this, For example, as shown in FIG. The electric current sintering apparatus 110 provided with (the 1st electric power supply roll 120, the 2nd electric power supply roll 130, and the 3rd electric power supply roll 140) may be sufficient. In this case, when the peripheral speed V1 of the first power supply roll 120, the peripheral speed V2 of the second power supply roll 130, the peripheral speed V3 of the third power supply roll 140, and the shrinkage rate X in the width direction of the sheet-like molded body F are set. , V1 × (100−X) / 100 <V2 <V1 × 1.1, and V2 × (100−X) / 100 <V3 <V2 × 1.1. It is preferable to set the peripheral speed V1 of the first power supply roll 120, the peripheral speed V2 of the second power supply roll 130, and the peripheral speed V3 of the third power supply roll 140 by 162 and 163.

Moreover, although demonstrated as what was provided with the 1st press roll control part and the 2nd press roll control part which control the circumferential speed of a 1st press roll and a 2nd press roll, it is not limited to this, These The holding roll may be a driven roll.
Further, the power supply roll is disposed on the lower side and the pressing roll is disposed on the upper side. However, the present invention is not limited to this, and the power feeding roll is disposed on the upper side and the pressing roll is disposed on the lower side. May be. Further, one of the first power supply roll and the second power supply roll may be disposed on the upper side and the other may be disposed on the lower side.

DESCRIPTION OF SYMBOLS 10 Electric current sintering apparatus 11 Sintering chamber 12 Inlet 13 Manufacture outlet 14 Electric power feeding mechanism 20 1st electric power feeding roll (electric power feeding roll arrange | positioned at the inlet side)
30 Second power supply roll (power supply roll placed on the outlet side)
40 First presser roll (presser roll)
50 Second presser roll (presser roll)
61 1st power supply roll controller (control mechanism)
62 Second power supply roll controller (control mechanism)

Claims (6)

It is a method for producing a sintered metal body by heating and sintering a sheet-like molded body made of metal powder to produce a sheet-like metal sintered body,
A sintering chamber provided with an inlet for charging the sheet-like molded body and a manufacturing outlet for producing the metal sintered body, and disposed at the inlet side and the outlet in the sintering chamber; At least a pair of power supply rolls for running the sheet-shaped molded body and supplying electricity to the sheet-shaped molded body; and a power supply mechanism for supplying electricity to the sheet-shaped molded body via the pair of power supply rolls. Using the electric current sintering device provided,
According to the shrinkage in the running direction accompanying the sintering of the sheet-shaped molded body, the peripheral speed of the power feeding roll disposed on the charging inlet side and the power feeding roll disposed on the outlet side is adjusted, and the sheet The sheet-like molded body is self-heated and sintered by energizing the sheet-like molded body through the pair of power supply rolls in a state where tensile stress is applied to the sheet-like molded body. A method for producing a sintered metal body. Shrinkage rate in the width direction when the sheet-shaped molded body is sintered with the peripheral speed of the power supply roll disposed on the inlet side being V1, the peripheral speed of the power supply roll disposed on the outlet side being V2 Is X%,
V1 × (100−X) / 100 <V2 <V1 × 1.1
The peripheral speed V1 of the power feeding roll arranged on the loading inlet side and the peripheral speed V2 of the power feeding roll arranged on the outlet side are adjusted so as to have the relationship A method for producing a sintered metal body. Before performing the electric sintering using the electric sintering apparatus, the electrical resistivity P of the sheet-like molded body is in the range of 10 × 10 ⁻⁶ Ω · m ≦ P ≦ 1500 × 10 ⁻⁶ Ω · m. It adjusts to these, The manufacturing method of the metal sintered compact of Claim 1 or Claim 2 characterized by the above-mentioned. An electric current sintering apparatus for energizing and sintering a sheet-like molded body made of metal powder by self-heating,
A sintering chamber provided with an inlet for charging the sheet-like molded body and an outlet for producing the metal sintered body;
At least a pair of power supply rolls disposed in the sintering chamber and on the outlet side in the sintering chamber for supplying electricity to the sheet-shaped molded body while running the sheet-shaped molded body,
A power supply mechanism for supplying electricity to the sheet-like molded body through the pair of power supply rolls,
An electric firing characterized by comprising a control mechanism that independently controls the peripheral speed of the power supply roll disposed on the loading side and the peripheral speed of the power supply roll disposed on the outlet side. Bonding device.   5. The electric current sintering according to claim 4, wherein a cooling path is formed in the power supply roll, and a cooling mechanism for cooling the power supply roll by circulating a refrigerant in the power supply roll is provided. apparatus.   2. A press roll for clamping the traveling sheet-shaped molded body together with the power supply roll, and a pressure adjusting mechanism for adjusting a clamping pressure between the press roll and the power supply roll. The electric current sintering apparatus of Claim 4 or Claim 5.

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