JPH0243334A - Platinum alloy for ornament - Google Patents

Abstract

PURPOSE:To improve hardness and flowability to precision parts by adding small amounts of Re and one or more elements among Ti, Zr and V to a Pt-Pd alloy with a specific composition. CONSTITUTION:A platinum alloy for ornament is constituted so that it has a composition consisting of, by weight, 80-98% Pt, 1-19% Pd, 0.5-10% Re, and further 0.05-3% of one or more elements among Ti, Zr and V. By the addition of Re to the Pt-Pd alloy, the effects of inhibiting the occlusion of gas in molten metal, refining the structure after casting, and increasing mechanical strength can be obtained. Further, attractive white color can be maintained without deteriorating the color tone of the Pt-Pd alloy. Moreover, by the addition of Ti, Zr and V, the effects of Re addition are increased and machinability is improved. This platinum alloy is used for ornaments, such as necklace, bracelet, tiepin, ring, and earrings.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to necklaces, bracelets, tie pins,
This invention relates to platinum alloys used for ornaments such as rings and earrings.

[Prior Art] Conventionally, binary alloys containing 1 to 20% of Pd have been most commonly used as decorative platinum alloys.

(Problems to be Solved by the Invention) Although this binary alloy has excellent plastic deformability and castability, it has low hardness and mechanical strength, and poor machinability, resulting in the following disadvantages.

In other words, when used for rings and necklaces, there is a problem that they are easily scratched and deformed, and when processing methods that require high cutting performance, such as diamond cutting, stickiness occurs, making it difficult to cut with good reflective properties. There is a problem with not being able to get a face.

Furthermore, with regard to jewelry worn with jewelry called stoneware, the strength of the claws that hold the jewelry is weak, which may lead to an accident in which the jewelry falls off.

In most cases, jewelry such as rings, tie pins, and brooches go through a brazing process, but the heating during this process causes the material to soften, making the strength of the parts particularly problematic.

Therefore, in order to improve the hardness of the Pt-Pd alloy, it is known to add about 2 to 5% Cu to make a ternary alloy, but this alloy has the problem of a blackish tone. be.

[Means for solving the problem] The present invention adds 0.5 to 10 wt% of Re to 1 to 19 wt% of Pd and 1 to 19 wt% of Pd, and further adds Ti,
It is characterized by adding 0.05 to 3 wt% of one or more of Zr and (2).

The addition of Re to the Pt-Pd alloy has the effect of suppressing gas occlusion in the molten metal, refining the structure after casting, and increasing mechanical strength.
A beautiful white color can be maintained without damaging the color tone of the alloy.

Furthermore, when one or more of Ti, Zr, and (2) is added to the above alloy, the effect of adding Re to the Pt--Pd alloy can be promoted and the machinability can be significantly improved.

Here, the reason why the amount of Re added is limited to 0.5 to 10 wt% is that if the amount of Re added is 0.5 wt%, the improvement in hardness and mechanical strength is insufficient. , 10
This is because if it exceeds wt%, the melting point becomes too high, making melting and casting difficult.

On the other hand, if the amount of one or more of Ti, Zr, and
This is because blowholes are likely to occur inside the cast body.

Moreover, if it is less than 0.05 wt%, a synergistic addition effect with Re cannot be expected.

〔Example〕

Pt47.5gXPd1.25g, Re0.75g, T
i 0.5 g was cast into a dendritic shape using a high-frequency suction precision casting machine using the lost wax casting method, and P t 95. Ow t%, P d 2.5 w t
%, Re 1, 5 wt %, and Ti 1.0 wt % were obtained.

Next, Pt49. Og, Pd0.675g, Re0.
25g, Ti0.025g, Zr0.025g, V0.
025g was cast into a dendritic shape using a high-frequency suction precision casting machine using the lost wax casting method to obtain the Pt shown in the table.
98.0wt%, Pd1.35wt%, Re0.5w
t%, T i 0.05w t%, Z r 0.05
w t %, V 0.05 w t % of B was obtained.

Hereinafter, L was obtained from C in the same manner.

The hardness of this dendritic cast body, the flowability to precision parts, the degree of occurrence of blowholes, and the casting surface of the cast body were observed and compared with alloys A to II made by the prior art.

Table The above table shows the components, Vickers hardness, and castability of the mustard A of this example and the conventional alloy A to II.

As shown in this table, while the hardness of the 95% Pt-Pd binary alloy is 65, this example has a hardness of 101 to 105, which is also 90%.
While the hardness of the Pt-Pd binary alloy is 70, this example has a hardness of 14.
0 to 148, similarly hardness of 85% PtPd binary alloy 90
On the other hand, in this example, the hardness was 163 to 175, indicating that the hardness was significantly improved.

Moreover, when comparing the castability, the cast body surface (casting surface) of this example is beautiful and there are fewer blowholes.

Furthermore, it has good flowability into precision parts and exhibits excellent castability.

(Effects of the Invention) According to the present invention described in detail above, 1. By adding Re to the Pt-Pd alloy and further adding one or more of Ti, Zr, and V, the hardness is significantly improved, and precision parts are This will greatly improve liquidity.

It also has the effect of suppressing gas occlusion in the molten metal, making the structure after casting finer, increasing mechanical strength, and creating a beautiful casting surface with fewer cavities.

Claims (1)

[Claims] 1. Re in Pt80-98wt%, Pd1-19wt%
A platinum alloy for decoration, characterized in that 0.5 to 10 wt% of Ti, Zr, and V are added, and 0.05 to 3 wt% of one or more of Ti, Zr, and V are added.