JPH0726340A - Gold ornament material hardened by alloying with small amount of component - Google Patents

Abstract

PURPOSE:To produce a gold ornament material having such hardness that it is hard to scratch while maintaining aesthetic value such as color tone and high-grade appearance peculiar to pure gold by alloying pure gold of >=99% purity with small amts. of specified metals. CONSTITUTION:Pure gold of >=99% purity is alloyed with 550-20,000ppm Ca and 10-200ppm La by melting the metals and the resulting alloy is drawn to form a wire having such hardness of >=100Hv that it is hard to abrade or scratch. The hardness of this alloy wire is not reduced even by heating to 450 deg.C brazing temp. required as an ornament and undergoes no change with the laspe of time.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention has a Vickers hardness (Hv) of 100 or more which is hard to be scratched or scratched, and has a high Vickers hardness even after a lapse of time or after heating such as brazing. The present invention relates to a gold ornament material that retains hardness.

[0002]

2. Description of the Related Art Conventionally, pure gold having a purity of 99% or higher, Ag, Cu, Ni, Pd,
Au alloys having a hardness of Hv: 100 or more are widely used as K14 alloys and K18 alloys by containing alloy components such as Zn and Zn in an amount of 25 to 40% by weight.

[0003]

On the other hand, it is ideal that the above-mentioned ornaments are made of pure gold in terms of color tone and luxury, but pure gold has an Hv of about 32 in an ingot state.
The processed wire has a hardness of about Hv: 80, and even if it is processed and hardened, the hardness not only decreases with the passage of time, but also the hardness cannot be reduced by heating such as brazing. As such, since pure gold ornaments are always in a soft state, they are easily scratched, and it is extremely difficult to maintain a high aesthetic value for a long period of time. Therefore, its application is limited to a very narrow range. .

[0004]

Therefore, the present inventors have
From the above viewpoint, as a result of conducting research to impart high hardness to the pure gold ornaments without losing the above high aesthetic value, pure gold having a purity of 99% or more, as an alloy component, Ca: 550-2 in proportion to the whole
When 000 ppm and La: 10 to 200 ppm are contained, the hardness is improved to Hv: 100 or more, and this high hardness is maintained over time and after heating such as brazing, and the content of the above alloy components is contained. Since the amount is small, the color tone and high-class feeling of pure gold are maintained, and thus the resulting gold ornament made of hard gold has the same high aesthetic value as pure gold ornament for a long time. I got the result of the research.

The present invention has been made based on the above research results, and in pure gold having a purity of 99% or more, Ca: 550 to 2000 ppm in the total ratio.
, La: 10 to 200 ppm, and is characterized by a gold ornament material made of hard gold.

In the gold decorative material of the present invention, the purity of pure gold is set to 99% or more. When the purity is less than 99%, the golden color tone of pure gold is impaired and the high-grade feeling is lost. The reason is that they will be punished. In addition, the contents of Ca and La are Ca: 550, respectively.
.About.2000 ppm and La: 10 to 200 ppm, as described above, the hardness is increased to Hv: 100 or more in the state of coexistence with these two components, and the increased hardness decreases with time and the decrease due to heating. Has a suppressing effect,
Therefore, even if the content of either of these components is less than Ca: 550 ppm and La: less than 10 ppm, the desired effect cannot be obtained for the above-mentioned action, and on the other hand, in any of the content, Ca: It is based on the reason that when it exceeds 2000 ppm and La: 200 ppm, the color tone and the high-grade feeling are impaired, and the aesthetic value is lowered.

[0007]

EXAMPLES Next, the gold decorative article material of the present invention will be specifically described by way of examples. In a normal vacuum melting furnace, pure gold having the purity shown in Table 1 is melted, and the same as in Table 1
The content of Ca and La shown in Fig. 2 was added, and then cast into a cylindrical ingot with a diameter of 20 mm and a length of 100 mm, and a test piece was cut out from the end of the ingot to obtain hardness (micro Vickers hardness (Load: 100gr)
After measuring, cut the surface and send it to a single-head wire drawing machine.
The gold decorative material materials 1 to 9 of the present invention are obtained by repeatedly performing a wire drawing process of a path to form a wire having a diameter of 0.5 mm.
In addition, pure gold ornament materials were manufactured under the same conditions except that Ca and La were not included.

[0008]

[Table 1]

Then, the hardness (micro Vickers hardness, load: 100 gr) of each of the various ornamental materials obtained as a result was measured immediately after wire drawing and after 6 months, and the decoration immediately after wire drawing was performed. Ordinary brazing conditions for the product material, that is, as a brazing material, for example, melting point: 370 ° C. A
u: 3 wt% Si alloy brazing filler metal, Au with melting point: 350 ° C.
Using a -12% Ge alloy brazing material or the like, the hardness was measured under the same conditions as in the case where the temperature was maintained at 450 ° C for 30 minutes and the heat treatment was performed under the conditions corresponding to the cooling conditions. The results of these measurements are shown in Table 1.

[0010]

From the results shown in Table 1, the gold decorative material materials 1 to 9 of the present invention have a high hardness of Hv: 100 or more, which does not change with time or by heating, and the hardness Is H
It is clear that when v: 100 or less, the hardness stability is remarkably superior to that of the pure gold decorative material material in which the hardness decreases with time and the hardness decreases due to heating. As described above, the gold decorative material of the present invention has a high hardness of Hv: 100 or more that is hard to be scratched, and this high hardness is stable with time and heating, and always Hv: 100 or more. Since it is maintained and the content of alloying components is small, it has the same aesthetic value as the excellent aesthetic value of pure gold and has the high hardness, so that the aesthetic value is maintained for a long time. It has useful characteristics such as

Claims (1)

[Claims] 1. A minor component characterized by comprising hard gold containing Ca: 550 to 2000 ppm and La: 10 to 200 ppm in pure gold having a purity of 99% or more in proportion to the whole. Gold decoration material hardened by alloying.