JPH1060558A - Gold alloy and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce high quality gold alloy harder than pure gold and furthermore having noble feeling and color tone equal to those of pure gold. SOLUTION: This hardened gold alloy has the compsn. contg., by weight, >=0.06% Pd, >=0.03% Ge, in which the total content of Pd and Ge is regulated to <=1%, and the balance substantial Au. Furthermore, as for the method for producing the gold, an alloy having a compsn. contg >=0.06% Pd, >=0.03% Ge, in which the total content of Pd and Ge is regulated to <=1%, and the balance substantial Au is subjected to solution treatment at 700 to 800 deg.C according to necessary, is thereafter subjected to aging treatment at 200 to 500 deg.C for 10 to 60min and is hardened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to ornaments such as rings, necklaces and watches, nibs, dental materials, medical instruments, and the like.
Regarding hardened gold alloys for use in electronic equipment and measuring instruments, and their manufacturing methods, more specifically, by adding small amounts of components, without losing the luster, metal color, beauty, weight, and luxury of gold The present invention relates to a high-grade gold alloy having increased hardness and a method for producing the same.

[0002]

2. Description of the Related Art Since high-grade gold alloys are soft, ornaments made of high-grade gold are easily damaged during processing and use, and it is difficult to maintain the original high-grade appearance. For example, a pure gold ingot has a micro Vickers hardness HV of about 30. For this reason, so-called 18K or 14K, which is obtained by adding 25 to 40% by weight of silver (Ag), copper (Cu) and the like and hardening, has been used for gold ornaments such as rings and necklaces.

[0003]

However, the so-called 18
K, 14K, etc., were inferior in their luster, metal color, beauty, weight, luxury, etc. to pure gold.

[0004] Therefore, an object of the present invention is to obtain a high-grade gold alloy which is harder than pure gold and has the same high-grade appearance and color tone as pure gold.

[0005]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that palladium (Pd) can be added to gold (Au) in an amount of 0.1%.
At least 0.6% by weight, at least 0.03% by weight of germanium (Ge), and a total content of Pd and Ge of at most 1% by weight. We have found that a high-grade gold alloy with the same high-grade appearance and color tone as pure gold decorative materials can be obtained.

That is, the gold alloy of the present invention has a Pd of 0.1.
Not less than 0.6% by weight and not less than 0.03% by weight of Ge,
The total content of d and Ge is 1% by weight or less, and the balance is substantially Au.

Further, the method for producing a gold alloy according to the present invention comprises the steps of:
Alloy containing 0.06% by weight or more of Ge, 0.03% by weight or more of Ge, a total content of Pd and Ge of 1% by weight or less, and the balance being substantially Au,
It is characterized by being subjected to aging treatment at a temperature of 10 ° C. for 10 to 60 minutes to harden.

[0008] Another method for producing a gold alloy of the present invention is as follows.
An alloy containing 0.06% by weight or more of Pd and 0.03% by weight or more of Ge, a total content of Pd and Ge of 1% by weight or less, and the balance substantially consisting of Au is 700 to 80%.
After solution treatment at a temperature of 0 ° C., aging treatment is performed at a temperature of 200 to 500 ° C. to harden.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Pd and G in the gold alloy of the present invention
e is added to harden soft pure gold, and the gold alloy is hardened as a synergistic effect of the addition of these two components.
The Pd content needs to be 0.06% by weight or more, and the Ge content needs to be 0.03% by weight or more. If Pd is less than 0.06% by weight or Ge is less than 0.03% by weight, a sufficient curing effect cannot be obtained. Also, Pd and G
The total content of e must be 1% by weight or less. When the total content of Pd and Ge exceeds 1% by weight, the composition is cured, but the quality of gold is reduced.

[0010] The gold alloy of the present invention is further hardened by aging treatment. It is thought that the aging treatment becomes harder at lower temperatures, but it is not preferable in production because it takes a longer time to obtain a certain hardness as the aging treatment at lower temperatures. Therefore, the temperature of the aging treatment is preferably 200 ° C. or higher. When aging treatment is performed at a temperature higher than 500 ° C., age hardening cannot be obtained. Therefore, the temperature of aging treatment is 500 ℃
The following is preferred.

The aging time varies depending on the composition and the aging temperature, but generally less than 10 minutes is less effective.
Since 0 minutes is sufficient, it may be appropriately selected in the range of 10 to 60 minutes.

Further, in cast products such as large cast products in which segregation of solute elements is often observed, age hardening may not be sufficiently obtained. Therefore, a solution treatment is performed before aging treatment to eliminate solute element segregation. By doing so, age hardening can be sufficiently exhibited. The solution treatment is performed at a temperature at which the solute element is solid-dissolved in gold, but it is preferable to perform the solution treatment at a higher temperature in terms of production since the solution can be formed in a short time. Therefore, the optimum temperature varies depending on the composition, but generally the solution temperature is 700-8.
The temperature may be set to 00 ° C.

[0013]

The present invention will be described below in more detail with reference to examples. First, Au-Pd-based and Au-Ge-based master alloys containing 1% by weight of each element of Pd or Ge were prepared in a high-frequency vacuum melting furnace, and these mother alloys and pure gold (purity 99.9) were prepared.
9%). Next, the raw materials blended so as to have a predetermined composition were melt-cast in a high-frequency vacuum melting furnace.
A gold alloy having the composition shown in Table 2 was produced. These ingots were subjected to an aging treatment at each temperature (Examples 1 to 5, Comparative Examples 1 to 4), and after being subjected to a solution treatment at each temperature, an aging treatment was performed at each temperature (Examples). 6, Example 7),
The ingot before aging and the hardness (micro Vickers hardness, load: 200 gf) at each aging time were measured.
The results are shown in Tables 1 and 2, together with the hardness of pure gold having a purity of 99.99% by weight.

[0014]

[Table 1]

[0015]

[Table 2]

From Tables 1 and 2, the gold alloy of the present invention was subjected to aging treatment, after which it was subjected to pure gold (purity: 99.99% by weight) and Comparative Examples 1-4.
It can be seen that the resin has been significantly hardened as compared with.

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

[0018]

The gold material for decorative articles of the present invention is harder than pure gold and has a small amount of alloying components, so that it is resistant to scratches and does not impair the luxury and color tone of pure gold. In addition, since a hard high-grade gold alloy can be manufactured by heat treatment after casting without performing processing such as rolling, the degree of freedom in design is increased, and it is possible to manufacture a gold ornament having a complicated shape.

Claims (6)

[Claims] 1. The method according to claim 1, wherein the content of Pd is 0.06% by weight or more and the content of Ge is 0.1% by weight.
A gold alloy containing at least 03% by weight, the total content of Pd and Ge being at most 1% by weight, and the balance being substantially Au. 2. Pd is 0.06% by weight or more and Ge is 0.02% by weight or more.
3% by weight or more, and the total content of Pd and Ge is 1
An age hardened gold alloy having a weight percent or less, with the balance being substantially Au. 3. The method according to claim 1, wherein Pd is 0.06% by weight or more and Ge is 0.1% by weight.
At least 03% by weight, the total content of Pd and Ge is at most 1% by weight, and the balance is substantially Au;
A hardened gold alloy that has been subjected to an aging treatment for 10 to 60 minutes at a temperature of 0 to 500 ° C. 4. The method according to claim 1, wherein Pd is 0.06% by weight or more and Ge is 0.1% by weight.
At least 03% by weight, the total content of Pd and Ge is at most 1% by weight, and the balance is substantially Au;
After solution treatment at a temperature of 0 to 800 ° C, 200 to 5
A hardened gold alloy that has been subjected to aging treatment at a temperature of 00C for 10 to 60 minutes. 5. The method according to claim 1, wherein Pd is 0.06% by weight or more and Ge is 0.1% by weight.
An alloy containing at least 03% by weight, the total content of Pd and Ge being at most 1% by weight, and the balance being substantially Au, is subjected to an aging treatment at a temperature of 200 to 500 ° C. for 10 to 60 minutes to harden. A method for producing a gold alloy, comprising: 6. Pd is 0.06% by weight or more and Ge is 0.1% by weight.
An alloy containing 0.3% by weight or more, the total content of Pd and Ge being 1% by weight or less, and the balance being substantially Au is subjected to a solution treatment at a temperature of 700 to 800 ° C.
A method for producing a gold alloy, comprising aging at a temperature of 0 to 500 ° C. to harden the alloy.