JPH06179931A - Decorative member made of hard au alloy high in au content - Google Patents

Abstract

PURPOSE:To obtain an Au allay decorative member free from the deterioration of hardness caused by working while the color tone and noble feeling characteristic of pure gold are maintained by incorporating Au with trace amounts of Ca and Fe as hardening allay components. CONSTITUTION:The content of Au is regulated, by weight, to >=99%, and, as hardening components, 500 to 2000ppm Ca and 0.1 to 10ppm Fe are incorporated to obtain a decorative member made of a hard Au allay. This Au alloy has high hardness of >=100HV hardly to flow by the coexisting action of Ca and Fe contained by trace amounts and can maintain high aesthetic value over a long period.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention has a high Vickers hardness (Hv) of 100 or more, which is hard to be scratched or scratched, even though the Au content is as high as 99% by weight. The present invention relates to a decorative member made of a hard Au alloy that hardly deteriorates in hardness over time and by heating such as brazing.

[0002]

2. Description of the Related Art Conventionally, decorative members generally used for manufacturing neck chains, broaches, finger rings, etc.
For the purpose of improving the hardness of Hv: 100 or more on pure gold,
K14 alloy or K containing about 25 to 40% by weight of alloy components such as Ag, Cu, Ni, Pd, and Zn.
It is well known that it is made of Au alloy such as 18 alloy.

[0003]

On the other hand, it is ideal that the above decorative member is made of pure gold in terms of color tone and high quality, but pure gold has an Hv of about 32 in the ingot state and a Hv of the processed wire. : The hardness is only about 80, and even when it is work hardened, the hardness not only decreases with the passage of time, but also the hardness cannot be reduced by heating such as brazing, which causes scratches. Since it is easy to wear and it is extremely difficult to maintain a high aesthetic value for a long period of time, the application as a decorative member has been very limited until now.

[0004]

From the above-mentioned viewpoints, the present inventor has found that Au having a high hardness of Hv: 100 or more, which is hard to be scratched while maintaining the golden color tone and high-grade feeling of pure gold. As a result of research to develop an alloy decorative member, the decorative member was found to have an Au content of 99% by weight or more,
When an Au alloy containing Ca: 500 to 2000 ppm and Fe: 0.1 to 10 ppm as an alloy component is used, the resulting Au alloy decorative member has a pure gold content of 99% by weight or more. The color tone and high-grade feeling are maintained, and the co-action of Ca and Fe, which are contained in a small amount as alloying components, makes it hard to be scratched. That is the result of the research.

The present invention has been made based on the above-mentioned research results. When the Au content is 99% by weight or more, the hardening alloy components are Ca: 500 to 2000 ppm, Fe: 0.1 to 10 ppm. Is characterized by being a hard Au alloy decorative member composed of an Au alloy containing.

In the decorative member of the present invention, the Au content of the Au alloy composing the decorative member is set to 99% by weight or more because when the content is less than 99% by weight, the gold color tone of pure gold is increased. The reason is that it is not possible to hold the product and the high-class feeling is lost. Further, the contents of Ca and Fe are each Ca: 500 to 20
00ppm and Fe: 0.1-10ppm is defined as
As described above, the hardness of both these components is H when they coexist.
v: It has an effect of increasing the hardness to 100 or more and suppressing the decrease in the increased hardness with time and the decrease due to heating. Therefore, even if the content of either of these components is less than Ca: 500 ppm and If the Fe content is less than 0.1%, the desired effects cannot be obtained, and if the contents exceed Ca: 2000 ppm and Fe: 10 ppm, the above effects do not show any further improving effect. The reason is that it becomes difficult to maintain the Au content at 99% by weight or more.

[0007]

EXAMPLES Next, the decorative member of the present invention will be specifically described by way of examples. Using an ordinary vacuum melting furnace, Au alloy and pure gold each having the composition shown in Table 1 were melted and cast into a cylindrical ingot having a diameter of 20 mm and a length of 100 mm. After collecting a sample for hardness measurement from the end of the, scraped and sent to a single-head wire drawing machine,
Here, 20 passes of wire drawing are repeatedly performed to obtain a diameter:
The decorative members 1 to 9 of the present invention and the pure gold decorative member were manufactured by processing into a wire of 0.5 mm.

With respect to the decorative members 1 to 9 of the present invention and the pure gold decorative members obtained as a result, the micro-Vickers hardness (load: 100 gr) was measured immediately after processing and after 6 months. Attachment conditions, that is, as a brazing material, for example, melting point: 370 ° C. A
u-3 wt% Si alloy brazing material and melting point: Au at 350 ° C.
Micro Vickers hardness (load: 100 gr) was measured under the condition of heating at a temperature corresponding to a brazing condition of 12% Ge alloy brazing material: 450 ° C. for 30 minutes and then cooling. . The results of these measurements are shown in Table 1.

[0009]

[Table 1]

[0010]

From the results shown in Table 1, the pure gold decorative member has a hardness as low as Hv: 100 or less, and has a remarkable decrease in hardness over time and a decrease in hardness due to heating. It is clear that each of the members 1 to 9 has a hardness of Hv: 100 or higher, and there is almost no decrease in hardness over time and hardness due to heating, and that a high hardness of Hv: 100 or higher is maintained. is there. As described above, since the decorative member of the present invention has a high Au content of 99% by weight or more, it has the same golden color tone and high-grade feeling as pure gold, and has a high hardness of Hv: 100 or more that is hard to scratch. Since it has a hardness decrease over time and a hardness decrease due to heating such as brazing, when it is put into practical use as various ornaments,
It has industrially useful properties such as maintaining these aesthetic values for a long period of time.

Claims (1)

[Claims] 1. An Au alloy characterized by comprising an Au content of 99% by weight or more and containing, as hardened alloy components, Ca: 500 to 2000 ppm and Fe: 0.1 to 10 ppm. A decorative material made of high-hard Au alloy.