JPH1060557A - 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, >=0.03% Rh, >=0.01% Al, in which the total content of Rh and Al is regulated to <=1%, and the balance substantial Au. Furthermore, as for the method for producing the gold alloy, an alloy having a compsn. contg. >=0.03% Rh, >=0.01% Al, in which the total content of Rh and Al is regulated to <=1%, and the balance substantial Au is subjected to solution treatment at 800 to 900 deg.C according to necessary, is thereafter subjected to aging treatment at 400 to 600 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 rhodium (Rh) is added to gold (Au) in 0.0.
3% by weight or more, aluminum (Al) 0.01% by weight
And the total content of Rh and Al is 1
It has been found that a high-grade gold alloy that is hard and has the same high-grade appearance and color tone as a pure gold decorative material can be obtained by using an alloy whose balance is substantially equal to or less than weight% and whose balance is substantially made of gold.

That is, the gold alloy of the present invention has a Rh of 0.1.
Not less than 03% by weight and not less than 0.01% by weight of Al
The total content of h and Al is 1% by weight or less, and the balance is substantially Au.

Further, the method for producing a gold alloy of the present invention comprises the steps of:
Alloy containing 0.03% by weight or more of Al, 0.01% by weight or more of Al, a total content of Rh and Al 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 0.03% by weight or more of Rh, 0.01% by weight or more of Al, a total content of Rh and Al of 1% by weight or less, and substantially Au as the balance is 800 to 90%.
After solution treatment at a temperature of 0 ° C., aging treatment is performed at a temperature of 400 to 600 ° C. to harden.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Rh and A in the gold alloy of the present invention
l 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 Rh content needs to be 0.03% by weight or more, and the Al content needs to be 0.01% by weight or more. If Rh is less than 0.03% by weight or Al is less than 0.01% by weight, a sufficient curing effect cannot be obtained. Also, Rh and A
The total content of 1 must be 1% by weight or less. If the total content of Rh and Al 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 400 ° C. or more. When aging treatment is performed at a temperature higher than 600 ° C., age hardening cannot be obtained. Therefore, the aging temperature is 600 ° C
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 solution temperature is 800-9.
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-Rh-based and Au-Al-based master alloys containing 1% by weight of each element of Rh or Al were prepared in a high-frequency vacuum melting furnace, and these master alloys and pure gold (purity 99.99) were prepared.
%) As raw materials. Next, the raw materials blended to have a predetermined composition were melt-cast in a high-frequency vacuum melting furnace to produce gold alloys having the compositions shown in Tables 1 and 2. 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 Rh is 0.03% by weight or more and Al is 0.1% by weight.
A gold alloy containing at least 0.1% by weight, the total content of Rh and Al is at most 1% by weight, and the balance substantially consisting of Au. 2. The method according to claim 1, wherein Rh is 0.03% by weight or more, and Al is 0.1% by weight.
Age-hardened gold alloy containing at least 0.1% by weight, the total content of Rh and Al is at most 1% by weight, and the balance is substantially Au. 3. The method according to claim 1, wherein the content of Rh is 0.03% by weight or more and the content of Al is 0.1% by weight.
0.1 wt% or more, the total content of Rh and Al is 1 wt% or less, and the balance is substantially Au.
A hardened gold alloy that has been subjected to an aging treatment at a temperature of 0 to 600 ° C for 10 to 60 minutes. 4. The method according to claim 1, wherein Rh is 0.03% by weight or more, and Al is 0.1% by weight.
At least 01% by weight, the total content of Rh and Al is at most 1% by weight, and the balance is substantially Au;
After solution treatment at a temperature of 0 to 900 ° C, 400 to 6
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 the content of Rh is 0.03% by weight or more and the content of Al is 0.1% by weight.
An alloy containing at least 01% by weight, the total content of Rh and Al being 1% by weight or less, and the balance being substantially Au is subjected to aging treatment at a temperature of 400 to 600 ° C. for 10 to 60 minutes to obtain a hard alloy. A method for producing a gold alloy, comprising: 6. The method according to claim 1, wherein the content of Rh is 0.03% by weight or more and the content of Al is 0.1% by weight.
An alloy containing at least 01% by weight, the total content of Rh and Al being at most 1% by weight, and the balance being substantially Au is subjected to a solution treatment at a temperature of 800 to 900 ° C.
A method for producing a gold alloy, comprising performing aging treatment at a temperature of 0 to 600 ° C. to harden the alloy.