JP2679268B2 - Manufacturing method of brazing material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a brazing material, and more particularly to an Ag-Al-Cu based brazing material containing Ag, Al and Cu as main components.

B. Summary of the Invention The invention is based on Ag (silver), Al (aluminum), Cu (copper).
Is a brazing filler metal of Ag-Al-Cu system containing 25 to 80% by weight of Ag powder and 14 to 75% by weight of Al powder,
This is a method for producing a brazing material, in which a mixed powder of 1 to 30% by weight of Cu powder is compression molded into a thin plate shape.

C. Conventional technology A brazing material is generally used for joining metals, and the brazing material at that time is in the form of a line (line brazing) or a plate (plate brazing) that is easy to handle. It is commonly used.

As the components of the brazing material, there are various types that can be selected according to the conditions of the joining metal and the like.

D. Problems to be Solved by the Invention Generally known Ag-Al brazing material is Ag95-Al5.
(% By weight), and this brazing material has a brazing temperature of about 900 ° C., which may adversely affect the joining member and other components thermally.

Thus, when Al is contained in an amount of 20 to 50% by weight, about 566 ° C.
It will have a eutectic point to some extent, and as the brazing temperature,
There is an advantage that the temperature can be reduced to about 650 ° C, which has less adverse effects on heat.

However, when Al is contained in an amount of 6 to 7% by weight or more, an intermetallic compound (for example, Ag3Al) is formed, which is hard and does not extend, and cannot be processed by rolling, etc.
It cannot be processed into a plate material (for example, 0.1 to 0.5 mm).

Therefore, a low-temperature Ag-Al brazing material (eg, Ag70-
If Al30) is required, the metal powder of each component must be mixed and used in the state of this mixed powder (or with some processing) before use.

For this reason, there is a problem that the handling is complicated, the application place is limited, and the stability of the bonding property is insufficient.

E. Means for Solving the Problems The inventors tried to form a thin film brazing material by plasma spraying Ag and Al powders.

As a result, a relatively good thin-film Ag-Al brazing material could be formed, but the following problems were newly found.

Insufficient strength to process into arbitrary shape.

For example, when brazing Cu members, part of the Al is Cu
It may diffuse into the member and deviate from the initial composition of the brazing material, and cracks may occur in the joint portion depending on the thickness of the brazing material.

Since the raw material is sprayed, there is a problem that there is a loss of the raw material and there is a difference between the set initial composition and the finished composition.

Therefore, the inventors have tried to add Cu to solve the above problems. As a result, 25-80% by weight Ag and 14-
It has been found that if the brazing material is formed of 75 wt% Al and 1 to 30 wt% Cu, the above problems can be solved and good brazing characteristics can be obtained.

The present invention comprises 25-80% by weight of Ag powder and 14-75% by weight of
It is a method for producing a thin plate-shaped brazing material obtained by compression molding a mixed powder of Al powder and 1 to 30% by weight of Cu powder.

However, when Ag, Al, and Cu are out of the above range (less than or more than the above range), the properties of each component become remarkable, and the brazing property and the bonding property decrease sharply. Is.

The composition of the brazing material is 30 to 58% by weight of Ag, 26 to 60% by weight of Al, and 10 to 25% by weight of Cu to obtain the best brazing property result.

In addition to Ag, Al, and Cu, other components added to improve brazing property in accordance with unavoidable impurities and joining metals may be contained.

The powder preferably has a particle size of −100 mesh or less (149 μm or less). Also, Al may explode or ignite if it becomes a fine powder in the atmosphere (in the presence of oxygen), so the particle size is 20 μm.
m or more.

The shape of the compression-molded body can be any shape using a mold, and the compression-molded body can be obtained by compression-molding into a ring shape or a circular shape, for example, according to the shape of the brazed portion. Alternatively, the plate obtained by compression molding is processed into a desired shape by means such as laser processing.

F. Action Since the mixed powder of the raw materials is compression molded into a thin plate shape, it is possible to easily obtain a brazing material of any shape in the mold shape,
Moreover, since it is compression-molded, the shape is not impaired during handling when arranging the brazing material, and it is possible to easily obtain an Ag-Al-Cu based brazing material with no restrictions on the applicable locations.

G. Examples The present invention will be described in detail based on examples.

Ag powder (80 g) and Al powder (160 g) with a particle size of 325 mesh or less (-325 mesh), grammage so that the component ratio is Ag: Al: Cu = about 40:40:20 (wt%) ) And Cu powder (40g)
And are prepared, and these powders are thoroughly mixed with a mixer.

Approximately 1.5 g of the obtained mixed powder was taken, uniformly filled in a mold having a diameter of 40 mm, and pressure-molded at 30 tons to obtain a circular thin plate-shaped brazing material having a thickness of 0.4 mm. .

This brazing material is used in vacuum (10 ^-5 torr) and 650
As a result of trying joining the Cu members together at a temperature of ℃, it was confirmed that the flow of the brazing material was good and the joining was sufficient.

Next, the brazing materials having various compositions were manufactured under the same conditions as those described above except for the components, and a joining experiment was conducted.

As a result, if the composition range shown in the figure, that is, 25 to 80% by weight of Ag, 14 to 75% by weight of Al, and 1 to 30% by weight of Cu, good brazing characteristics are obtained. On the other hand, the factors that deteriorate the brazing characteristics such as "crack" and "peeling" at the brazed portion remarkably occurred.

On the other hand, especially 30 to 58 wt% Ag, 26 to 60 wt% Al, Cu
When 10 to 25% by weight, a strong connective structure was obtained and stable brazing property results could be obtained.

H. Effect of the Invention Since the brazing material of the present invention is compression-molded with a mixed powder of raw materials Ag, Al and Cu, a thin plate-shaped Ag-Al brazing material can be easily obtained.

Moreover, by selecting the shape of the mold, it is possible to easily obtain a brazing material having an arbitrary shape, and it is possible to obtain a plate-shaped brazing material having no restriction on the applicable position.

Also, since the brazing temperature is a relatively low brazing temperature of about 650 ° C, it is possible to reduce the thermal effect on the joining member and other constituent members, and not only copper but also iron and stainless steel. Good joining of members made of various metal materials such as steel, Kovar alloy, titanium and nickel.

Therefore, the present invention can be widely applied to various brazing portions of vacuum equipment, power equipment (for example, vacuum interrupter, GTO), electronic equipment, industrial equipment, and the like, and can improve productivity and reduce cost.

[Brief description of the drawings]

The figure is an explanatory view of the composition range of a useful brazing material based on the experimental results.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-32494 (JP, A) JP-A-3-32492 (JP, A) JP-A-3-32489 (JP, A) JP-A-3- 32488 (JP, A) JP-B-44-27451 (JP, B1) Patent 2605841 (JP, B2)

Claims (1)

(57) [Claims] 1. A brazing material containing Ag, Al and Cu as main components, which comprises 25 to 80% by weight of Ag powder, 14 to 75% by weight of Al powder, and 1.
A method for producing a brazing material, which comprises compression-molding a mixed powder containing 30 to 30% by weight of Cu powder into a thin plate shape.