JPH11792A - High grade gold solder material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable brazing without impairing high grade feeling, color tone, etc., incidental to pure gold by constituting a gold solder such that Co and Ge are incorporated by a specific weight% or above and that the balance is Au by a specific weight% or above. SOLUTION: The solder is designed to contain not less than 0.5 wt.% each of Co and Ge, with the balance Au by 95 wt.% or above. Co and Ge are added for the purpose or lowering the melting point 1,063 deg.C of pure gold and increasing the strength of the filler metal itself. Both of these effects are attained by the combined addition of Co and Ge, which are required to be not less than 0.5 wt.% each. If either Co or Ge is less than 0.5 wt.%, it makes the melting point of the filler metal higher and its strength lower, preventing the use as the filler metal. Meantime, Au needs to be contained for 95 wt.% or above; otherewise, gold is degraded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-grade gold brazing material for a gold alloy used for decorative articles such as rings, necklaces, watches and the like, dental materials, medical instruments, electronic instruments, measuring instruments and the like.

[0002]

2. Description of the Related Art In recent years, it has the luxury and color tone of pure gold,
Also, hardened high-grade gold alloys such as 23K and 24K have been developed. 18K, 14K, 12K or the like to which 25 to 50% by weight of silver (Ag), copper (Cu), or the like is added has been used as a brazing material for these high-grade gold alloys.

[0003]

However, 18K, 14K, 12K, etc. used in conventional brazing materials are inferior in their luster, metal color, beauty, weight, luxury, etc. as compared with pure gold. When brazing a high-grade gold alloy, the use of these low-grade brazing materials not only causes a color difference from the material but also lowers the quality of the entire product. For this reason, there has been a demand for a high-grade gold brazing material having the color tone and luxury of pure gold.

[0004] Therefore, the present invention provides a sense of quality equivalent to pure gold,
An object of the present invention is to provide a high-grade brazing material having a color tone or the like.

[0005]

A high-grade brazing filler metal of the present invention for solving the above-mentioned problems contains 0.5% by weight or more of Co, 0.5% by weight or more of Ge, and the remaining 95% by weight. %
It is characterized by the above Au.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Co and Ge in the high-grade gold brazing material of the present invention are added to lower the melting point of pure gold of 1063 ° C. and to increase the strength of the brazing material itself. Both of these effects can be obtained by adding Co and Ge in combination. Both Co and Ge need to be added in an amount of 0.5% by weight or more. If Co is less than 0.5% by weight or Ge is less than 0.5% by weight, the melting point of the brazing material is high and the strength of the brazing material itself is low, so that it cannot be used as a brazing material. On the other hand, the content of Au is 95
It is necessary that the content be at least% by weight. If the content is less than 95% by weight, the quality of gold is reduced.

[0007]

The present invention will be described below in more detail with reference to typical examples.

First, Co or Ge is used in a high frequency vacuum melting furnace.
Au-Co-based alloy containing 1% by weight of each element of Au and Au
A Ge-based alloy was manufactured as a master alloy. Next, a raw material obtained by mixing these mother alloys and pure gold having a purity of 99.99% to have a predetermined composition is melt-cast in a high-frequency vacuum melting furnace.
A gold alloy having the composition shown in Table 1 was used. Next, the melting point of each gold alloy and the strength of the brazed portion were measured. The strength of the brazed portion was measured by brazing two pieces of 5 × 25 × 0.3 mm pure gold (purity: 5N) using 10 mg of each gold alloy shown in Table 1 as a brazing material and using an autograph.

[0009]

Table 1------------------------Co content (% by weight) Ge content (% by weight) Melting point (° C.) ------------------------------------------------------------------------------------- Example 1 0.95 0.93 750 Example 2 1.54 1.49 700 Example 3 1.54 1.49 675 Example 4 2.45 2.42 659 −−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−

[0010] As shown in Table 1, the gold alloy of the present invention comprises:
Despite high quality, pure gold (purity 5N, melting point 1063)
° C) and K18 (composition by weight%, Au-12.5Ag-
12.5 Cu, melting point 885 ° C.). Further, as a result of the measurement of the brazing portion strength, not only the brazing portion but also the material portion of all the materials of Examples 1 to 4 were broken, and the material had a sufficient peel strength.

The gold alloy of the present invention has a luster, a metallic color,
Beauty, weight, luxury, etc. are no different from pure gold.

[0012]

The high-grade gold brazing material of the present invention can be brazed without impairing the high-grade appearance and color tone of pure gold because the amount of elements added to gold is small.

Claims (1)

[Claims] 1. Co is 0.5% by weight or more and Ge is 0.5% by weight.
A high-grade gold brazing filler metal containing at least 95% by weight of Au and at least 95% by weight of Au.