JP3578833B2 - Gold alloy for jewelry - Google Patents

Description

【００１０】
表１に示す各試料は、まず、実施例に示す添加元素であるＰ，ＳｉおよびＳｍを主元素とした合金をアーク溶解にて鋳造して母合金とした。
つぎに、純Ａｕに実施例に示す組成で上記母合金を配合し、上記同様アーク溶解を行い、厚さ１０ｍｍ， 幅３０ｍｍ， 長さ５０ｍｍのケーキ状の鋳造体とし、この鋳造体を、熱間鍛造で線用、板用に成形し、所定の形状まで加工を行って試料とした。
【００１１】
その結果、表より明らかな如く、各実施例は純Ａｕに比べて硬さが高い。
【００１２】
【発明の効果】
以上詳細に説明した本発明によると、Ａｕと称呼できる程の微量の添加元素組成でも、純Ａｕに比べてほぼ同等の耐蝕性や純Ａｕ特有の光沢をもち、しかも硬さや機械的強度が高く、また添加量の多い場合は飛躍的に機械的特性の上昇となる効果を有し、宝飾用ばかりでなく、電子部品、医療分野等広い範囲で有用な金材料となる。[0001]
[Industrial applications]
The present invention relates to a gold alloy for jewelry in which a hardness is increased by adding a trace element to pure Au.
[0002]
[Prior art]
Au has excellent corrosion resistance and spreadability, and is widely used in jewelry and the like because of its elegant color.
[0003]
[Problems to be solved by the invention]
However, pure Au has a problem that it is very flexible and has low hardness and low mechanical strength, so that the surface is easily scratched and easily deformed.
[0004]
[Means for Solving the Problems]
Therefore, the present invention is characterized in that P contains 5 to 1000 ppm, Si 10 to 200 ppm, Sm 10 to 200 ppm, and the balance consists of 99.5% by weight or more of Au and an impurity element. 5 to 1000 ppm, Si is 10 to 200 ppm, Sm is 10 to 200 ppm, and one or more of Sb, Cu, Zn, Fe, Co, Ni, Ga, Ag, and Ge are used as sub-addition elements, and these sub-addition elements are added in total. At least 10 ppm, and the total of these sub-additional elements and impurity elements contains 5,000 ppm or less, and the balance is made up of 99.5% by weight or more of Au .
[0005]
The reason why P, Si and Sm are added elements is to improve the hardness after casting and after processing.
Sb, Cu, Zn, Fe, Co, Ni, Ga, Ag, and Ge, which are sub-additional elements, have an effect on fluidity during casting, and have an effect on making crystals finer and improving hardness.
The reason why the added amount of the added element is 5 to 1000 ppm for P, 10 to 200 ppm for Si, and 10 to 200 ppm for P is not effective in improving hardness when P is 5 ppm, Si and Sm are less than 10 ppm, and P1000 ppm, Si and Sm are not effective. If it exceeds 200 ppm, it becomes too hard and becomes brittle.
[0006]
If the amount of the sub-additive element is less than 10 ppm, the above effect cannot be obtained. If the total amount of the sub-additive element and the impurity element exceeds 5,000 ppm, the quality of gold deteriorates, and the so-called pure This is because the gold color of Au is lost.
[0007]
[Action]
According to the present invention described above, the hardness after casting is improved as compared with pure Au due to the action of the additional element, and the increase in hardness due to work hardening in plastic working such as processing of a plate or wire is increased.
[0008]
【Example】
Examples of the present invention are shown in Table 1 below, and pure Au is also shown as a conventional example.
[0009]
[Table 1]

[0010]
Each sample shown in Table 1 was obtained by casting an alloy containing P, Si, and Sm, which are the additional elements shown in Examples, as main elements by arc melting.
Next, the above-described mother alloy was mixed with pure Au with the composition shown in the example, and arc melting was performed in the same manner as described above to obtain a cake-like casting having a thickness of 10 mm, a width of 30 mm, and a length of 50 mm. It was formed into a wire or plate by cold forging and processed to a predetermined shape to obtain a sample.
[0011]
As a result, as is clear from the table, each example has a higher hardness than pure Au.
[0012]
【The invention's effect】
According to the present invention described in detail above, even with a trace amount of additive element composition that can be referred to as Au, it has almost the same corrosion resistance and luster unique to pure Au as compared to pure Au, and has high hardness and mechanical strength. Also, when the addition amount is large, it has the effect of dramatically increasing the mechanical properties, and is a gold material useful not only for jewelry but also for a wide range of fields such as electronic parts and medical fields.

Claims (2)

A jewelry gold alloy containing 5 to 1000 ppm of P, 10 to 200 ppm of Si, and 10 to 200 ppm of Sm, with the balance being 99.5% by weight or more of Au and an impurity element . P is 5 to 1000 ppm, Si is 10 to 200 ppm, Sm is 10 to 200 ppm, and at least one of Sb, Cu, Zn, Fe, Co, Ni, Ga, Ag, and Ge is used as a sub-addition element. A total of 10 ppm or more, the total of these sub-additional elements and impurity elements is 5000 ppm or less, and the balance is Au of 99.5% by weight or more .