JP2010047787A - Method for producing solder-impregnated sheet material and production device therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a solder-impregnated sheet material which has reduced internal defects (blow holes) by impregnating a porous metal body with solder without voids. <P>SOLUTION: The method comprises: a step where foamable slurry comprising metal powder and a foaming agent is formed into a sheet shape to be foamed, and is thereafter sintered to form a porous metal body 2; and a step where the porous metal body 2 is dipped into a solder tank 13 storing solder in a melted state for 1 to 3 s, and vibration of 150 to 400 Hz is applied to the porous metal body 2 in the dipped state, thus the porous metal body 2 is impregnated with the solder. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention is a method and a method for producing a solder-impregnated sheet material, which is used for joining a circuit board and a semiconductor element, and in which a porous metal body having a three-dimensional network structure is impregnated with a skeleton of a metal sintered body. Relates to the device.

Generally, when an electronic component or the like is joined to a substrate with solder, soldering by a flow or reflow method is performed. However, in recent years, due to the problem of high heat generation due to the improvement in the degree of integration and performance of semiconductors and the difference in stress caused by the difference in thermal expansion coefficient from the laminated body such as copper and aluminum laminated for heat dissipation, solder There are concerns about problems such as the occurrence of cracks in the attachment site.
In order to solve these problems, the present applicant made a three-dimensional network skeleton body with a metal excellent in thermal conductivity, electrical conductivity, low expansibility, etc., and impregnated this metal skeleton body with solder. The technique described in Patent Document 1 has been proposed as a technique for reducing the thermal stress generated at the joint and suppressing the occurrence of cracks and the like by using the sheet material.

The technique described in Patent Document 1 is applied to a solder joint portion of a power module substrate. In this power module substrate, a circuit layer is brazed to an insulating substrate such as a ceramic substrate, and a semiconductor element is fixed on the circuit layer via a solder-impregnated sheet material. And forming a foamable slurry containing a foaming agent into a sheet and foaming it, followed by sintering to form a porous metal body having a three-dimensional network structure by the skeleton of the metal sintered body, In this configuration, a porous metal body is impregnated with solder.
Japanese Patent Laid-Open No. 2004-29862

By the way, when impregnating such a porous metal body with solder, unlike the case of soldering simple plane materials, a foam having a three-dimensional fine skeleton structure is simply soldered due to the difference in surface area. When immersed in molten metal, there are many problems such as adhesion of fine bubbles on the surface due to adsorption, etc., and in the case of a thick porous body, it is difficult for solder to enter the inside and it is difficult to remove adsorbed bubbles. To do. As a result, it was impossible to obtain a product that would generate many defects in the impregnated body and obtain desired characteristics.
As an improvement measure, we tested the preheating temperature, the solder heating temperature, the immersion time, the selection of the flux, etc. when impregnating the porous metal body, but in any combination, completely eliminate the void defects inside the impregnation layer. Was not a sufficient measure. In particular, the problem has been further highlighted by changing the solder material from Pb—Sn solder to Pb-free solder.

  The present invention has been made in view of such circumstances, and an object thereof is to obtain a solder-impregnated sheet material having few internal defects by impregnating a porous metal body with solder without any gap.

  The present invention is a method for producing a solder-impregnated sheet material by impregnating a plate-like porous metal body having a three-dimensional network structure with a skeleton of a metal sintered body, and containing a metal powder and a foaming agent. The foamable slurry is formed into a sheet and foamed, and then sintered to form a porous metal body, and the porous metal body is placed in a solder bath for storing the solder in a molten state for 1 second. Immersing the porous metal body with solder by immersing for 3 seconds and applying vibrations of 150 Hz to 400 Hz to the porous metal body in the immersed state.

By immersing the porous metal body in the molten solder and applying vibration to the porous metal body, the porous metal body peels innumerable fine bubbles adsorbed on the porous metal body and on the surface of the porous metal body from the skeleton. It is possible to improve the soundness by moving and expelling the space. The reason why the immersion time is set to 1 to 3 seconds is that when the immersion time is less than 1 second, the solder is not sufficiently filled in the porous space and there is not enough time for air bubbles to escape.
On the other hand, the reason why the frequency was set to 150 Hz to 400 Hz is that if the frequency is less than 150 Hz, the force that peels off the adsorbed bubbles from the skeleton is difficult to act, and the bubbles do not move sufficiently in the skeleton. This is because when the frequency exceeds 400 Hz, the skeleton of the porous metal body heated in the molten solder is softened and the deformation of the skeleton structure is accelerated, and desired characteristics cannot be obtained.

In the method for producing a solder-impregnated sheet material of the present invention, it is preferable that an impact is applied to the porous metal body after the porous metal body is pulled up from the solder bath.
Immediately after pulling up from the solder bath, the solid metal or the solder attached to the part holding the porous metal body drips and generates droplets, forcing a shock. In this way, it is possible to remove these drops, which leads to improvement in product yield, appearance and solder saving.

Moreover, in the method for producing a solder-impregnated sheet material of the present invention, it is preferable that the molten solder overflows on the surface of the solder bath at the position where the porous metal body is immersed.
By overflowing the molten solder, there will always be a fresh molten solder without any oxide on the surface of the molten metal where the porous metal body is immersed, and the solder adheres to the porous metal body. And the cleanliness of the surface of the impregnated sheet material can be improved.

  Furthermore, in the method for producing a solder-impregnated sheet material of the present invention, before the porous metal body is impregnated with solder, the surface of the porous metal body is coated with a nickel film, preferably electrolytic Ni plating (electroless depending on the material or use application). (It may be plating.) It is preferable to have a step of forming a film. By forming a high-purity Ni film on the entire skeleton of the porous metal body by electrolytic plating, the wettability of the solder is improved, and a wider impregnation is possible under the solder impregnation conditions. In particular, when copper is used as the porous metal body, the reaction time with the lead-free solder can be increased, so that it is greatly involved in the structural stability and soundness of the impregnated body.

The apparatus for producing a solder-impregnated sheet material of the present invention is an apparatus for producing a solder-impregnated sheet material by impregnating a plate-like porous metal body having a three-dimensional network structure with a skeleton of a sintered metal body. A solder bath having a heating means for storing solder in a molten state, a hand member for gripping the porous metal body, and the hand member is moved up and down to immerse the porous metal body in the solder bath, Elevating and lowering means for pulling up and vibration applying means for applying vibration to the porous metal body via the hand member are provided.
Further, in the manufacturing apparatus of the present invention, the hand member is delivered to and from the lifting means at a position above the solder tank, and the hand member is retreated from the position above the solder tank and the position above the solder tank. It is preferable that there is provided a transfer means that moves between the two positions, and an impact applying means that applies an impact to the hand member when the hand member is delivered from the elevating means to the transfer means.

Further, in the solder impregnated sheet material manufacturing apparatus of the present invention, the solder tank is provided with a cylindrical frame having a flat opening into which the porous metal body can be inserted in the surface direction, and the opening is provided in the opening. It is preferable to have a configuration in which jetting means for flowing the molten solder from below toward the overflow from the upper end of the cylindrical frame is provided.
By making the solder melt overflow in the flat opening, there will always be a fresh solder melt surface without oxide on the surface of the opening, and the solder adheres to the porous metal body. Can be sure. In addition, the overflow state is formed in a limited range of only the flat opening, and the efficiency is high.

  According to the present invention, by applying vibration while the porous metal body is immersed in the solder bath, a large number of fine bubbles and bubbles adsorbed on the skeleton that have entered the voids of the porous metal body are forced. In addition, the porous metal body can be impregnated with solder without any gaps, and a solder-impregnated sheet material with few internal defects can be obtained.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
The solder-impregnated sheet material will be described in advance. The solder-impregnated sheet material 1 is obtained by impregnating a porous metal body 2 made of copper, for example, with a solder 3 as shown in FIG. It is made up of. The porous metal body 2 has a three-dimensional network structure in which a plurality of polyhedrons whose sides are formed by a skeleton 2a of a sintered metal body is formed in a continuous state, and is formed in a rectangular plate shape as a whole. ing.
The porous metal body 2 has a thickness of 0.3 mm to 3 mm (in fact, it can be rolled so that it can be processed into an arbitrary dimension), and the void 2b formed between the skeletons 2a has a porosity (porous). The percentage of the actual weight of the porous metal body with respect to the weight of the solid body having the same shape as the porous metal body) is set to 50% to 90%. The average opening diameter (equivalent circle diameter of the opening) on the outer surface is set to 150 μm to 600 μm. A Ni plating film 4 is formed on the surface of the skeleton 2 a of the porous metal body 2.

In order to produce the porous metal body 2, a foamable slurry is prepared by mixing a metal powder, a foaming agent, a binder (water-soluble resin binder), water, and a surfactant as necessary. For example, the foamable slurry can be formed into a sheet by a doctor blade method, foamed under a constant temperature and high humidity condition, and then sintered.
FIG. 6 shows a green sheet forming apparatus 5 for producing the porous metal body 2. The green sheet forming apparatus 5 transfers the foamable slurry F from the hopper 6 that stores the foamable slurry F to the carrier sheet 7. The green sheet G is formed by being fed to the top and conveyed by the carrier sheet 7 while being molded to a predetermined thickness by the blade 8, foamed in the constant temperature / high humidity tank 9, and dried by the drying tank 10. The porous metal body 2 is sintered.
After the nickel coating 4 is formed on the porous metal body 2 by electrolytic plating, it is immersed in a solder bath and impregnated with solder as will be described later, whereby the solder-impregnated sheet material 1 is obtained.

Next, an embodiment of an apparatus for manufacturing the solder-impregnated sheet material 1 by immersing the solder 3 in the porous metal body 2 will be described.
1-5 has shown the solder impregnated sheet material manufacturing apparatus of this embodiment. In the manufacturing apparatus 11, a solder tank 13 and a handling means 14 for the porous metal body 1 are supported on a gantry 12.
The solder tank 13 is formed in a rectangular shape such as a cube or a rectangular parallelepiped as a whole, and a heating means 15 such as a heater is provided at the bottom thereof. In addition, two cylindrical frames 16 and 17 are arranged inside the solder tank 13, and the molten solder S is circulated along the cylindrical frames 16 and 17. As shown in detail in FIG. 3, one cylindrical frame 16 has an L shape extending from the inner bottom portion of the solder bath 13 to the liquid surface, and the vertical portion thereof is an opening portion at the upper end portion thereof. 18 is opened upward in the upper part of the solder bath 13. The opening 18 is formed in a flat shape having a band shape slightly larger than the plate thickness of the porous metal body 2 and slightly longer than the width of the porous metal body 2, and is a vertically suspended porous body. The porous metal body 2 can be inserted vertically along the surface direction of the porous metal body 2 from above, and a slight gap is formed around the porous metal body 2 in the insertion posture.

  Further, the lower end portion of the cylindrical frame body 16 is opened laterally at the inner bottom portion of the solder tank 13, and another cylindrical frame body 17 is provided so as to surround the lower end opening portion 19. . The cylindrical frame 17 is a comparatively short one formed in a circular cross section, and is disposed on the inner bottom surface of the solder tank 13 in the vertical direction so that the one cylindrical frame 16 A vertical flow path communicating with the lower end opening 19 is formed. The upper opening 20 of the cylindrical frame 17 having a circular cross section is opened inside the solder tank 13, and the propeller 22 of the jet means 21 is disposed in the opening 20. The jet means 21 has a shaft 23 provided with the propeller 22 connected to a speed reducer 24 on the solder bath 13, and a motor 25 fixed to the side of the gantry 12 is connected to the speed reducer 24. The shaft 23 is rotated by the motor 25 via the speed reducer 24, and the propellant 22 propels the solder melt S in the solder bath 13 along the cylindrical frames 16 and 17 as indicated by the arrows in FIG. It is the structure to distribute.

As shown in FIGS. 1 and 2, the handling means 14 includes a hand member 31 that holds the porous metal body 2, an elevating means 32 that moves the hand member 31 up and down, immerses it in the solder bath 13, and pulls it up. The hand member 31 is transferred to and from the lifting means 32 at a position above the solder bath 13, and the hand member 31 is reciprocated between the position above the solder bath 13 and the side position retracted from the position above. It is set as the structure provided with the transfer means 33 to do.
As shown in FIG. 4, the hand member 31 has a pair of arms 35 extending in a direction perpendicular to the crosspiece member 34 attached to a strip-like crosspiece member 34, and one of the arms 35 is a crosspiece member 34. As shown by the arrow in FIG. 4, it can be swung around the attachment portion 36 as a center, and the porous metal body 2 is held between these arms 35. Both arms 35 are formed with groove portions 37 that engage with the porous metal body 2 at the opposing portions along the length direction, and the groove portions 37 are closed at the front end portions (lower end portions) of both arms 35. A receiving member 38 is provided. Further, a coil spring 39 that urges the swingable arm 35 in a direction to approach the other arm 35, and a backing material 40 that supports the upper end of the back surface of the porous metal body 2 held by both arms 35. Is provided. The arms 35 are made of pure Ti or stainless steel, which is said to have good corrosion resistance against lead-free solder. However, in order to ensure complete corrosion resistance, a spray-type ceramic mold release is used. A material or the like may be applied.

  As shown in FIG. 1, the elevating means 32 has a rail 45 extending in the vertical direction fixed to the gantry 12 at a position in front of the solder bath 13, and an upper and lower slider member 46 is provided on the rail 45 so as to be movable up and down. The upper and lower slider members 46 are provided with grip members 47 capable of gripping both ends of the cross member 34 of the hand member 31. The grip member 47 grips the cross member 34 of the hand member 31 and 35 can be moved up and down in a suspended state. In this case, as shown in FIG. 3, the grip member 47 moves vertically above the opening 18 of the solder tank 13 and holds the hand member 31 to descend. The operation of pulling up from the opening 18 is repeated by immersing the arm 35 of the hand member 31 from the opening 18 in the solder bath 13 and ascending it. The grip member 47 is provided with vibration applying means 48 such as a vibration motor for applying vibration to the grip member 47.

  On the other hand, the transfer means 33 is provided with a horizontal movement mechanism 51 such as a rodless cylinder that is driven in the horizontal direction above the solder tank 13, and is moved up and down at both ends of the horizontal slider member 52 in the horizontal movement mechanism 51. Two delivery mechanisms 53 and 54 for delivering the hand member 31 to and from the means 32 are provided. In these delivery mechanisms 53 and 54, an extrusion cylinder 55 that is driven in the front-rear direction is fixed to the horizontal slider member 52, and the crosspiece member 34 of the hand member 31 is placed on the tip of the piston shaft 56 of the extrusion cylinder 55. Claw members 57 and 58 for maintaining the state are provided via brackets 59 and 60. The push-out cylinder 55 reciprocates the claw member 57 between a position above the opening 18 of the solder tank 13 and a side position where the claw member 57 is retracted in the horizontal direction (front-rear direction) from the upper position. .

Further, of the both delivery mechanism portions 53 and 54, the first delivery mechanism portion 53 disposed on the right side in FIG. 2 includes one piece so as to support the central portion of the crosspiece member 34 of the hand member 31 from below. A claw member 57 is provided, and the second delivery mechanism portion 54 disposed on the left side of FIG. 2 has two claw members so as to support both ends of the crosspiece member 34 of the hand member 31 from below. 58 is provided. Further, as shown in detail in FIG. 5, these two claw members 58 are supported so as to be rotatable about a shaft 61 and are normally held in a horizontal posture in which both claw members 58 face each other. However, when these opposed end portions are pushed upward from below, they can be rotated in opposite directions so as to increase the distance between the opposed end portions. Each claw member 58 is provided with a biasing means (not shown) such as a spring that returns to the original horizontal posture when the pushing-up force is released.
Further, a guide member 62 is provided at a position above the both claw members 58 in the second delivery mechanism portion 54 to guide both ends of the crosspiece member 34 spanned between the claw members 58 so as to be slidable up and down. ing. These guide members 62 have gaps 63 that are large enough to allow the crosspieces 34 to slide up and down, and because the gaps 63 are set to be larger than the claw members 58, the claw members 58. It is designed not to obstruct the rotation.

  The transfer means 33 moves one of the transfer mechanism portions 53 and 54 to a position above the solder bath 13 by moving the horizontal slider member 52 of the horizontal moving mechanism 51 and moving in the front-rear direction by the pushing cylinder 55. These are alternately moved between an upper position of the solder bath 13 and a lateral position spaced apart in the horizontal direction, such that the other is disposed at a lateral position spaced apart in the horizontal direction. Is.

A method for manufacturing the solder-impregnated sheet material 1 by impregnating the porous metal body 2 with the solder 3 using the manufacturing apparatus 11 configured as described above will be described.
As described above, the green sheet G is formed from the foamable slurry F by the green sheet forming apparatus 5, and this is sintered to produce the plate-like porous metal body 2, and the nickel coating 4 is formed on the surface by electrolytic plating. Form it. Next, the porous metal body 2 on which the nickel coating 4 is formed is held by the hand member 31. Since the hand member 31 is opened by swinging one of the arms 35, the porous metal body 2 is interposed between the arms 35 and the arms 35 are closed to open both sides of the porous metal body 2. Is held in the groove 37 of the arm 35.

  On the other hand, in the solder impregnated sheet material manufacturing apparatus 11, the solder S is heated to, for example, 250 ° C. and stored in a molten state in the solder bath 13, and both delivery mechanism portions 53 and 54 are arranged on the right side of FIG. By placing the cross member 34 of the hand member 31 holding the porous metal body 2 on the claw member 57 of the first delivery mechanism 53, the hand member is placed on the delivery mechanism 53. 31 is supported in a suspended state. When the manufacturing apparatus 11 is operated in this state, first, the horizontal slider member 52 is moved horizontally by the horizontal movement mechanism 51, and the hand member 31 is moved above the opening 18 of the solder bath 13. At this time, the upper and lower slider members 46 of the elevating means 32 are kept waiting at the upper position of the rail 45, and the upper and lower slider members 46 are lowered, and the grip members 47 are attached to both ends of the cross member 34 of the hand member 31. Hold it. Then, the hand member 31 is slightly raised, and the claw member 57 is retracted by the push-out cylinder 55 of the delivery mechanism portion 53, so that the lower portion of the hand member 31 is opened, and the upper and lower slider members 46 move the hand member 31. As shown in FIG. 3, the porous metal body 2 is immersed in the molten solder S together with the hand member 31 from the opening 18 of the solder bath 13 as shown in FIG. 3.

In the solder tank 13, as described above, the molten solder S overflows from the opening 18 by the jet means 21, and the porous metal body 2 is vertically immersed in the liquid surface of the overflowed solder melt S. In the immersed state, vibration is applied to the hand member 31 by the vibration applying means 48 via the grip member 47. The porous metal body 2 is immersed in the solder bath 13 for 1 to 3 seconds, and vibrations with a frequency of 150 Hz to 400 Hz are applied therebetween.
During this immersion, the transfer means 33 is returned to the initial position, and the first transfer mechanism 53 that has transferred the hand member 31 to the solder tank 13 moves to the right side of FIG. The mechanism portion 54 is disposed above the solder tank 13, and the push-out cylinder 55 is operated to stand by in a state where the claw portions 57 and 58 are pushed forward. In this standby state, both the claw members 58 of the second delivery mechanism portion 54 are disposed above the opening 18 of the solder bath 13. The hand member 31 holding the new porous metal body 2 is placed on the first delivery mechanism 53 returned to the initial position.

  Then, when the hand member 31 is pulled up from the solder bath 13 by the lifting means 32, both end portions of the cross member 34 of the hand member 31 move the opposing end portions of the two claw members 58 of the second delivery mechanism portion 54 upward from below. By pushing up, as shown by a chain line in FIG. 5, both the claw members 58 are rotated so as to open the passage space of the crosspiece member 34, and after the crosspiece member 34 passes, it is returned to the horizontal posture by the restoring force of the spring. . The grip member 47 lifts the crosspiece member 34 to a position slightly higher than the two claw members 58 along the guide member 62 provided above the claw member 58, and then releases the gripping state of the crosspiece member 34. Thereby, the crosspiece member 34 is dropped along the guide member 62 on the claw member 58 returned to the horizontal posture, and an impact due to the drop is applied, and the impact is applied to the porous metal body 2. The excess portion of the molten solder S that has permeated is drained from the porous metal body 2 and dropped into the solder bath 13. In this embodiment, the impact applying means of the present invention is configured to adjust and apply the degree of impact during free fall by adjusting the lifting height of the hand member 31 and the weight of the hand member 31.

  After the hand member 31 is transferred to the second transfer mechanism 54 in this manner, the upper and lower slider members 46 are retracted to the upper standby position, and the horizontal slider member 52 moves the second transfer mechanism 54 to the solder bath 13. 2 is moved horizontally (to the left in FIG. 2), and the new porous metal body 2 placed on the first delivery mechanism 53 is moved to the upper position of the solder bath 13 along with the horizontal movement. Moved. On the other hand, the second delivery mechanism portion 54 is moved to the side position of the solder bath 13 indicated by the chain line in FIG. 2, the hand member 31 is removed, and then the second delivery mechanism portion 54 is retracted by the extrusion cylinder 55. The removed hand member 31 releases the porous metal body 2 after the solidification of the solder is completely completed, and the new porous metal body 2 is held. Thereafter, a series of these operations are repeated, and the porous metal body 2 is sequentially immersed in the solder bath 13 to manufacture the solder-impregnated sheet material 1.

Next, using this manufacturing apparatus, the solder was immersed under various conditions, and the occurrence of blow holes was observed.
As a porous metal body, an electrolytic Ni plating film is formed on a pure copper foam with a thickness of 0.5 μm, and a test sample having a nominal hole diameter of 300 μm, a sample size of 1 mm in thickness, 50 mm in width, and 100 mm in length Carried out. The solder melt temperature was fixed at 250 ° C., a solder-impregnated sheet material was prepared under the conditions shown in Table 1, and the soundness of each test piece was evaluated. In the evaluation method, approximately 20 mm square test specimens are collected from the approximate center of each specimen, and the cross section is mirror-polished. Using an optical microscope, all blowholes with a major axis of 20 μm or more are counted at a magnification of 100 times. did. The solder used is a lead-free solder of the trade name M705 (Sn-3Ag-0.5Cu) manufactured by Senju Metal Co., Ltd., and the trade name ES-1016 sparkle flux manufactured by Senju Metal Co., Ltd. is used as the flux. did.
After degreasing the porous metal body with a hydrocarbon solvent, the above-mentioned flux is applied with a pressure spray gun and then heated in an oven at 100 ° C. for 5 minutes to blow off the solvent and at the same time preheat the porous metal body Then, immediately after taking out, it was set on the hand member, and was impregnated with solder using the apparatus of the present invention to obtain a test piece. The evaluation test results are shown in Table 1.

  As can be seen from Table 1, the occurrence of blowholes that cause a practical problem in the cross section of each test specimen was hardly observed when the immersion time was 1 to 3 seconds and the vibration frequency was 150 to 400 Hz. In comparison with this, the occurrence of significant blowholes was confirmed in the test piece to which no vibration was applied. In the case where the frequency was 600 Hz or more or in the test piece to which ultrasonic vibration was applied, deformation of the test piece or partial dissolution of the test piece was observed. It is presumed that this is because too strong vibration was applied to the softened porous metal body in the solder bath.

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, in the above embodiment, the arm of the hand member is configured to hold and handle both sides of the porous metal body, but as another holding structure, such as holding and hanging the upper end of the porous metal body Also good. In addition, when the hand member lifted from the solder tank is delivered to the delivery mechanism unit, it is dropped on the claw member to give an impact to the porous metal body. However, the hand member in a stationary state is hit. The impact may be given by other methods. In addition, the detailed configuration of the transfer method and the like can be changed as appropriate.
Depending on the solder material, Pb-free solder that suppresses the generation of droplets has also been developed, and there is a case where the above-mentioned impact may not be applied. Judged to be good.

It is a longitudinal cross-sectional view which shows one Embodiment of the manufacturing apparatus of the solder impregnation sheet material which concerns on this invention. It is the arrow line view which abbreviate | omitted the grip member in alignment with the AA of FIG. It is an enlarged view of the part of the solder tank of FIG. It is a front view of a hand member used for a manufacturing device of one embodiment. The detail of the 2nd delivery mechanism part of FIG. 2 is shown, (a) is a front view, (b) is arrow sectional drawing in alignment with the BB line of (a). It is a schematic diagram of the green sheet shaping | molding apparatus for manufacturing a porous metal body. It is sectional drawing of a solder impregnation sheet material.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Solder impregnation sheet material 2 Porous metal body 2a Frame | skeleton 2b Space | gap 3 Solder 4 Nickel coating 5 Green sheet forming apparatus 11 Solder impregnation sheet material manufacturing apparatus 13 Solder tank 14 Handling means 15 Heating means 16, 17 Cylindrical frame 18 Opening DESCRIPTION OF SYMBOLS 21 Jet means 31 Hand member 32 Elevating means 33 Transfer means 34 Crosspiece member 35 Arm 47 Grip member 51 Horizontal movement mechanism 53,54 Delivery mechanism part 57,58 Claw member 62 Guide member S Solder molten metal

Claims (7)

A method for producing a solder-impregnated sheet material by impregnating a plate-like porous metal body having a three-dimensional network structure with a skeleton of a metal sintered body with solder,
Forming a foamable slurry containing a metal powder and a foaming agent into a sheet and foaming, and then sintering to form a porous metal body; and
By immersing the porous metal body in a solder tank for storing solder in a molten state for 1 to 3 seconds, and applying a vibration of 150 Hz to 400 Hz to the porous metal body in the immersed state, the porous metal body A method for producing a solder-impregnated sheet material comprising a step of impregnating a body with solder.   The method for producing a solder-impregnated sheet material according to claim 1, wherein an impact is applied to the porous metal body after the porous metal body is pulled up from the solder bath.   3. The method for producing a solder-impregnated sheet material according to claim 1, wherein a molten solder is overflowed on a surface of the solder tank at a position where the porous metal body is immersed.   4. The method according to claim 1, further comprising a step of forming a nickel film by electrolytic plating on a surface of the porous metal body before impregnating the porous metal body with solder. A method for producing a solder-impregnated sheet material. An apparatus for producing a solder-impregnated sheet material by impregnating a plate-like porous metal body having a three-dimensional network structure with a skeleton of a metal sintered body with solder.
A solder bath having a heating means for storing solder in a molten state;
A hand member for gripping the porous metal body;
Elevating means for elevating and lowering the hand member to immerse the porous metal body in the solder bath and pull it up;
An apparatus for producing a solder-impregnated sheet material, comprising vibration imparting means for imparting vibration to the porous metal body through the hand member. The hand member is transferred between the elevating means at a position above the solder tank, and the hand member is moved between an upper position of the solder tank and a side position retracted from the upper position. Means are provided,
6. The apparatus for producing a solder-impregnated sheet material according to claim 5, further comprising impact applying means for applying an impact to the hand member when the hand member is delivered from the elevating means to the transfer means. . The solder tank is provided with a cylindrical frame having a flat opening into which the porous metal body can be inserted in the surface direction, and a molten solder is circulated from below toward the opening to form a cylindrical frame. An apparatus for producing a solder-impregnated sheet material according to claim 5 or 6, wherein jetting means for overflowing from the upper end of the solder is provided.

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