JP2001198693A - Gold brazing filler metal for industrial use and jewel and ornament - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid development of a crack of a raw material which is brazed in a predetermined temperature range and a failure caused by generation of the migration phenomenon by preventing a precipitation hardening beyond a precipitation line of a gold-copper compound due to the formation of rule lattice of gold-copper and a rapid variation in the coefficient of thermal expansion in a prescribed temperature range with respect to a gold brazing filler metal for industrial use and jewels and ornaments. SOLUTION: The brazing filler metal is a gold brazing filler metal containing, by wt., 10 to 30% gold, 5 to 30% indium, and the balance copper, and the relative additions of compositions are regulated to avoid a rapid variation in the coefficient of thermal expansion in a prescribed temperature range. Generation of a rapid variation in the coefficient of thermal expansion due to the formation of rule lattice is avoided with respect to the gold brazing filler metal of the binary alloy of gold and copper specified in the Japan Industry Standard(JIS), thus development of a crack is prevented, the durability is excellent, the preservability is excellent, and the durability is excellent in terms of function.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The disclosed technology is a gold brazing technique suitable for brazing metals such as industrial goods such as ceramic products and high vacuum equipment, metal engraving products, jewelry such as watch cases and necklace jewels. Belongs to the field.

In particular, it belongs to the technical field of gold brazing as a jewelry material, which has a relatively high copper content and is suitable for brazing a gold alloy exhibiting a red color.

[0003]

2. Description of the Related Art Recently, gold brazing is used for joining vacuum equipment, metal engravings, and jewelry. For example, in the case of a gold-copper alloy, 40 to 85% of gold, silver, copper, zinc, indium is used. In the embodiment where is contained, in a certain set temperature range, gold and copper compounds due to the formation of a superlattice of gold-copper cause precipitation hardening beyond the set deposition line, but in order to avoid such phase transformation, As shown in FIG. 1, in a known service temperature range (for example, 400 to 450 ° C.), in a known brazing filler metal, a sudden change occurs in a coefficient of thermal expansion and a coefficient.
When brazing is performed between a substance and a joining metal, there is a defect that cracks occur depending on the material, brazing temperature, and a used temperature range, and a so-called migration phenomenon in which silver components due to silver content segregate to the cathode side. There is a problem that occurs.

When cadmium, zinc, and lead are added to a general gold solder to lower the melting point, a smoke phenomenon occurs and the vapor pressure increases, and consequently, in a vacuum of industrial goods or jewelry equipment, or However, there is a problem that it is unsuitable for brazing in a furnace.

[0005]

An object of the invention of this application is to solve the problems associated with the above-mentioned brazing based on the above-mentioned prior art, and is constituted by the metal element described in claim 1 of the preceding claims, and its characteristics are as follows. The gold-copper binary JIS gold brazing process is performed so that the coefficient of thermal expansion and coefficient do not change abruptly due to the formation of ordered lattices. It is an object of the present invention to provide an excellent industrial and jewelry brazing filler metal that can be used in the metal industry to benefit from the application of joining technology.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the structure of the invention of the present application for solving the above-mentioned problems is described below. With gold 10-30, indium 5-30
%, With the balance being made of copper, so that the weight ratio of the metal does not cause a rapid change in the coefficient of thermal expansion and coefficient in the operating temperature range.
Technical measures were taken so that the heat treatment was performed outside the temperature range of 00 to 450 ° C. in comparison with the prior art brazing filler metal.

[0007]

Thus, in the above-described structure, the phase transformation of the gold and copper compounds is avoided, and the generation of cracks is suppressed by preventing a rapid change in the coefficient of thermal expansion and coefficient from occurring.
In particular, in jewelry, for example, the color tone of reddish color is reduced.

[0008]

By the way, the reason why the content of gold is set to 10 to 30% is that, by removing the gold-copper regular lattice forming region from the results of the experiment, the gold content exceeds the gold and copper deposition line, and Is not caused, thereby increasing the coefficient of thermal expansion
It has been experimentally confirmed that a rapid change in the coefficient is suppressed.

Next, in order to lower the melting point, indium having a low vapor pressure is added, and the addition amount is set to 5 to 30%. When the addition amount is less than 5%, the effect of lowering the melting point is not experimentally recognized. This is because when it exceeds 30%, it has been found that workability cannot be obtained.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the embodiments of the present invention will be described with reference to the drawings by comparing the embodiments of the present invention with gold-copper binary JIS peripheral well-known gold solders. It is as follows.

First, in all samples, the compounding amount was set to 1,0.
In the example, as shown in FIG. 1, a relative amount addition of a composition component was performed so that the coefficient of thermal expansion and the coefficient did not suddenly change in a predetermined temperature range, and the resultant was obtained through ordinary melting casting. Cold and hot groove roll processing was performed from the obtained ingot, and after cutting to φ2.0 mm, each of the following samples subjected to annealing was used. In the material processing in a predetermined temperature range, as shown in FIG. 1, processing is performed in a range of 400 to 450 ° C.

The following Table 1 shows the gold alloys according to the embodiments of the present invention and the known examples A and B in comparison.

[Table 1]

A comparison between the above-mentioned known gold solder and the gold solder of the embodiment, and comparison of their melting points and results of color tone are shown in Table 2 below.

[Table 2]

It can be clearly seen that the addition of indium in Table 2 lowers the melting point.

As for the color tone, it was found that as the amount of indium added increased, the reddish color became lighter and the color tone became yellow.

Next, as shown in FIG. 1, the horizontal axis represents temperature (unit: ° C.), and the vertical axis represents the coefficient of thermal expansion / coefficient (unit: × 10 ^-6 ).
The data of the brazing filler metals of Examples 1 and 2 and the known examples A and B are as shown in the figure, and were subjected to a predetermined treatment in advance (the amount of the added elements was carefully set and set).
In the gold solders of Examples 1 and 2, a smooth curve is drawn in the range of the use temperature of 400 to 450 ° C., whereas in the gold solders of the known examples A and B, especially the gold solder of the known example B has a thermal expansion coefficient in the same range. Is remarkably changed, and it can be seen that there is a possibility that cracks may occur when the joining material is metal or the like.

Therefore, it can be said that it is suitable for the purpose of the invention of the present application to carry out the treatment by adding relative amounts of components having a composition in which the coefficient of thermal expansion and coefficient of thermal expansion do not change abruptly.

In the temperature range of 400 to 450 ° C., it is necessary to pay close attention to the relative compounding amounts of the added elements as compared with the known examples, and as a result, as shown in FIG. No abrupt changes occur.

[0019]

As described above, according to the invention of this application, gold is used in industrial and jewelry products in a weight ratio of 10 to 3%.
0%, 5-30% of indium, and the balance of copper by gold brazing, the gold-copper superlattice formation portion exceeded the gold and copper compound deposition line in a predetermined temperature range,
In the case where the precipitation effect does not occur and the material is brazed while avoiding phase transformation, the relative addition treatment of the compositional elements is performed so that a rapid thermal expansion coefficient and coefficient do not occur in a predetermined temperature range, for example, 400 to 450 ° C. By applying the composition, an excellent effect is obtained in that the original form is well formed without cracking and the durability is extended.

In addition, an excellent effect of good quality is obtained, which does not cause a problem of occurrence of migration due to silver content.

In addition, since no smoke is generated, the vapor pressure does not increase, and from this point, an excellent effect that brazing can be performed in a vacuum or in a furnace is achieved.

[Brief description of the drawings]

FIG. 1 is a graph showing a comparison between the thermal expansion coefficient and the coefficient of thermal expansion of a known gold solder and the temperature of a gold solder of an embodiment.

Claims (3)

[Claims] 1. A gold solder containing gold and copper, comprising 10 to 30% by weight of gold, 5 to 30% of indium, and the balance copper. 2. The industrial and jewelry gold solder according to claim 1, wherein the weight ratio of said metal does not cause a rapid change in the coefficient of thermal expansion and coefficient in the operating temperature range. 3. The industrial and jewelry gold according to claim 2, wherein the operating temperature range is set outside the temperature range of 400 to 450 ° C. and compared with that of the prior art brazing solder. Would.