JP3797637B2 - Composite - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a composite material by brazing mainly used in the electronics industry, semiconductor industry, metal mold relations, industrial machinery and the like.
[0002]
[Prior art]
It is considered an easy technique to firmly bond different metals to each other by brazing. This is because a lamellar brittle intermetallic compound is generated by melting of the bonding interface in the liquid phase bonding process, and is a phenomenon often seen in brazing. Therefore, the composite material having such a weak layer often peels off during processing or use, or causes problems such as separation or inability to be used as a composite plate.
[0003]
In order to solve the above problems, there is a brazing method using a coating method. For example, in Japanese Patent Laid-Open No. 8-257743, a nitride or carbide is previously coated on a joint surface of dissimilar metals and brazed, but even with this coating method, the thickness of the coating layer is limited, For example, if it is thin, a porous part is formed, and diffusion occurs from the part, resulting in formation of a brittle intermetallic compound, which cannot be completely avoided. Also, for example, in Japanese Patent Application Laid-Open No. 60-133971, brazing is performed after 5-100 μm of Al, Al—Si, Ag, Sn is coated on the joining surface of steel or stainless steel. Formation of fragile intermetallic compounds due to heat effects is unavoidable, and problems such as peeling during processing or use into a desired shape or separation have not been completely solved.
[0004]
[Problems to be solved by the invention]
In order to clarify the problem, the inventor of the present application observed the reaction part in the liquid phase joining process in detail and analyzed the composite material by brazing, which is a conventional method, and as a result, the formation of a fragile layered intermetallic compound In addition, it was confirmed that a gap of about 10 to 20 μm was present in a dotted and continuous manner at the interface between the brazing material and the material to be joined. That is, as a whole, the brazed boundary surface includes unreacted unreacted parts due to the wettability of the brazing material and the material to be joined, which can reach about 50% of the entire joining surface in a large case. Etc., and confirmed new problems that occurred outside the vulnerable part of the reaction part.
[0005]
As described above, the method of directly brazing dissimilar metals or the latest method of coating in advance cannot completely avoid the generation of fragile intermetallic compounds at the bonding interface, and 100% bonding is performed. It ’s difficult. Therefore, there have been many problems in manufacturing and use, such as peeling or separating the composite plate after joining into a desired shape or during use. Furthermore, the expected performance cannot be ensured in such a composite plate, and for example, various problems such as instability of conductivity during use and reduction in production efficiency due to deterioration occur. There are some uses that have not been done. The object of the present invention is to prevent the occurrence of unbonded portions between the brazing material and the base material as much as possible and prevent the formation of fragile intermetallic compounds. As a result, they are peeled off during processing into a desired shape and during use. It aims at providing the composite material which does not produce.
[0006]
[Means for Solving the Problems]
That is, the present invention
[1] A composite material in which two base metal materials are bonded to a joining auxiliary material via a brazing material, and at least one of the base metal materials is solid-phase bonded to the joining auxiliary material by explosive pressure bonding. A composite material characterized by
[ 2 ] The composite material according to [1], wherein the joining auxiliary material has a thickness of 0.5 to 6 mm.
As described above, the present invention is a composite material having a bonding auxiliary layer and a brazing material layer between base metal materials, and the bonding auxiliary layer and the metal material layer are solid-phase bonded. .
In the present invention, the base metal material refers to a metal material to be finally joined, and examples thereof include a metal plate material, a sintered material, a pressed material, and a forged material. Moreover, any kind of normally used metals such as steel, iron, copper, aluminum, tungsten (W), silver, nickel, titanium, molybdenum, niobium, tantalum, and alloys thereof can be used. In the present invention, a great effect is obtained when the base metal materials are different from each other, but the same kind of metal may be used. This is particularly effective in the case of a metal material obtained by sintering or pressing metal powder, in the case of a metal material that cannot be subjected to explosive pressure bonding, or in the case of a combination of base metal materials that are difficult to be solid-phase bonded.
[0007]
In the present invention, the joining auxiliary material is a metal that assists the joining of the base metal material and the brazing material, is a metal that can be solid-phase joined to the metal material to be joined, and has a wettability with the brazing material to be used. Ru good metal material der. For example, copper - when a tungsten alloy and steel to be bonded with a silver brazing material, copper is preferable, also, to an aluminum alloy and stainless be joined with an aluminum alloy brazing material, aluminum alloy is preferable. The thickness of the joining auxiliary material layer is preferably 0.11 to 10 mm, more preferably 0.5 to 6 mm, and particularly preferably in the range of 1 to 3 mm. If necessary, the bonding auxiliary layer may be solid-phase bonded to both base metal materials.
[0008]
Here, “good wettability” refers to a state in which when a liquid brazing material is placed on the metal surface, the familiarity between the two is good and the brazing material spreads in a thin film on the entire metal surface. Examples of the combination of the joining auxiliary layer and the brazing material having good wettability include Cu and silver brazing material, and Al alloy and Al alloy brazing material.
Solid-phase bonding refers to a method of bonding close to the range where the attractive force between atoms is applied, or bonding by the diffusion phenomenon of atoms, a method in which solid metal materials are pressed together at room temperature or under heating conditions, or an explosion and a method of bonding is not good.
[0009]
The joining auxiliary material is composed of a main component of either the brazing material or the base metal material. Here, the main component indicates a component having the largest ratio among a plurality of components.
Next, examples of composite materials are given. For example, when A and B are brazed using a brazing material C, if the wettability of each dissimilar metal and brazing material C is bad and good with A, A is preliminarily metallurgically solid-phase bonded to B. and left as an a + B, or the a + C + a + B by brazing material C, shall be the a + C + D + B by metallurgically bonded to the brazing material C leave the D + B good other metallic materials D material wettability with the brazing material C in advance B. When the wettability is poor with A and the wettability with B is good, A + B + C + B or A + D + C + B is set in the same way as described above. If both A and B have poor wettability, a metal material F having good wettability with A and a metal material G with good wettability are preliminarily metallurgically bonded to A with the same concept, and the brazing material C is used as A + F + C + G + B. That's fine.
[0010]
Further, in the obtained composite plate, it is confirmed whether or not a good bonding is performed on the surface where the metal material having good wettability is solid-phase bonded in advance and the liquid-phase bonding surface at the brazing portion is in accordance with JIS G 0601. It can be performed by sonic flaw detection, JIS Z 2343 penetration flaw detection test, and micro observation with a microscope.
The composite material according to the present invention is free from problems such as peeling or separation during processing into a required shape, and is improved in electrical conductivity by about 50%, and is particularly suitable for an electrode member for electric discharge machining.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example explains.
[0012]
[Example 1]
Prior to the copper plate to be brazed, an explosion that is a metallurgical joint with a thickness of 3 mm of a laminated copper plate C1100P of the same material as that having good wettability and a thickness of 30 mm of a base steel plate SS400, with a width x length of 1000 x 1500 mm Produced by the crimping method. 50 mm wide and 100 mm long from the clad plate, that is, (3 + 30) × 50 × 100 is cut out, and a good wettability copper C1100P thickness 3 mm side and a copper plate C1100P thickness 10 mm to be brazed are JIS Z 3261BAg-1 Were brazed with a silver brazing material, and a copper plate + silver brazing + copper plate + steel plate (10 + silver brazing + 3 + 30) × 50 × 100 mm composite plate was produced. As for the joining condition, it was confirmed that 100% pressure bonding was performed by ultrasonic flaw detection test of JIS G 0601 after explosive cladding, and after cutting to 50x100 mm, the joint end surface is defect-free by penetration test of JIS Z2343. Further, microscopic observation with a microscope was carried out with 10% sampling, and there was no brittle intermetallic compound and no microscopic gap, and it was very good. The joining surface of the brazing was also confirmed in the same manner as described above, and both the brazing surfaces were extremely well joined.
[0013]
However, a very small spot-like gap of about 10 μm, which was extremely small but could not be detected by the penetrant flaw test, was slightly confirmed by microscopic observation with a microscope. This situation was the same for the upper and lower parts of brazing, and no continuous gap was found as in the conventional method. From 50 × 100 mm, 50 pieces were cut out to a size of the original thickness × 7 × 10 mm and cut, but peeling and separation were not seen at all. Further, 50 of them were used as electrodes for electric discharge machining, but they were not peeled off or separated at all during use, and conduction and discharge were stable at a high level.
[0014]
[Example 2]
Prior to the metal material of the Cu 30% -W 70% alloy to be brazed, a width of 3 mm of the copper plate C1100P with good wettability is previously combined with the 30 mm thick surface of the base steel plate SS400 with poor wettability. The x length was 200 × 200 mm, and it was manufactured by the explosive pressure bonding method, which is metallurgical bonding. Cut out from the clad plate 45mm width, 95mm length, that is, (3 + 30) x45x95, and weighed a good wettability copper C1100P thickness 3mm side and Cu30% -W70% alloy plate thickness 10mm to be brazed, Brazing was performed with a silver brazing material of JIS Z 3261BAg-1, and a Cu 30% -W 70% alloy plate + silver brazing + copper plate + steel plate (10 + silver brazing + 3 + 30) × 45 × 95 mm composite plate was produced. As for the joining situation, it was confirmed that 100% crimping was performed by ultrasonic flaw detection test after JIS G 0601 after explosive cladding, and after cutting to 45 x 95 mm, the joint end face was defect-free by penetration test of JIS Z2343. Further, microscopic observation with a microscope was conducted, and there was no fragile intermetallic compound and no microscopic gap, and the result was extremely good. The joint surface of the brazing was also confirmed in the same manner as described above, and the Cu 30% -W 70% alloy side and the copper side were very good brazing.
[0015]
Although it was extremely small, a very small spot-like gap of about 10 μm that could not be detected by the penetrant flaw test was confirmed by microscopic observation on both brazed surfaces, but it was continuous as in the conventional method. No gaps were seen. Forty pieces were cut out from 45 × 95 mm to a thickness of the original thickness × 7 × 10 mm and cut, but peeling and separation were not observed at all. Further, 40 of them were used as electric discharge machining electrodes, but they were not peeled off or separated at all during use, and conduction and discharge were stable at a high level.
[0016]
[Comparative Example 1]
Basically, the same material as in Example 1 was used for comparison with the prior art. In other words, a C1100P thickness of 10 mm, a copper plate with good wettability, is placed opposite to the 30 mm thickness of the base steel plate SS400 with poor wettability, and the composite plate is brazed with a silver brazing material of JIS Z 3261BAg-1. Manufactured. The dimensions were the thickness of a copper plate, silver brazing, and steel plate (10 + silver brazing + 30), and the width x length was 50 × 100 mm. As for the bonding state, in the ultrasonic flaw detection test of JIS G0601 after brazing, although there seems to be a defect that seems to be unbonded, it could not be clearly determined. About 25% of point-like or continuous defects were observed between the steel plates.
[0017]
Furthermore, when partially cut out and observed with a microscope, some fragile intermetallic compounds are also found, and unbonded portions with a gap of 10 to 15 μm are seen as about 45% as point-like or continuous defects. It was. These unbonded parts are naturally found in the steel and the brazed part, while the copper part and the brazed part cannot be detected by a penetrant flaw detection test, but a very small spot-like gap of about 10 μm is observed by microscopic observation with a microscope. This was the same as in Example 1 with only slight confirmation. When 45 pieces were cut out from the composite plate to a size of 7 × 10 mm and cut, a joint opening, peeling, and separation were found in five pieces. The remaining 40 were used as electric discharge machining electrodes, but 6 openings in use were seen. This opening, peeling, and separation were all between steel and brazing material.
[0018]
【The invention's effect】
According to the present invention, the brittle intermetallic compound that has been seen in the brazed portion until now does not occur at all, and the unbonded portion newly confirmed by micro observation does not occur, so the bonding strength of the conventional product is weak. In addition to solving various problems, in addition, combinations that could not be brazed until now are possible, and cutting into a required shape as a composite material, during machining, bending, etc., or opening in use, There is no peeling, no separation, resulting in significant productivity improvement, no generation of defective materials, and economic effects can be expected, and it can be applied to various technical fields that could not be used so far. Development is also expected.

Claims (2)

A composite material in which two base metal materials are joined to a joining auxiliary material via a brazing material, and at least one of the base metal materials is solid-phase joined to the joining auxiliary material by explosive pressure bonding . A composite material characterized by The composite material according to claim 1, wherein the joining auxiliary material has a thickness in a range of 0.5 to 6 mm.