Method for obtaining a component made of a palladium-indium alloy having a good workability

1 . A method for obtaining a component made of a palladium (Pd)-indium (In) alloy comprising between 46 and 56 wt % Pd, between 44 and 54 wt % In, between 0 and 10 wt % of silver (Ag), gold (Au), copper (Cu), platinum (Pt), silicium (Si), or tin (Sn), or a combination of these elements, between 0 and 2 wt % of any one of: ruthenium (Ru), rhodium (Rh), rhenium (Re) or iridium (Ir), between 0 and 5 wt % of aluminum (Al), and a maximum of 1.5 wt % of other elements; the method comprising:

providing the Pd—In alloy;

thermomechanical processing the Pd—In alloy, comprising a step of hot pressing under vacuum, hot pressing under a protective gas, or hot isostatic pressing;

wherein the thermomechanical processing is performed at a heating temperature between 1050° C. and 1150° C., at controlled deformation rate of 0.1 to 100 mm/h with an applied load between 1 and 500 MPa; and

wherein the thermomechanical processing is performed with a deformation ratio between 1.2 and 15, the deformation being defined as the ratio of the initial lateral size of the component, prior thermomechanically processing the component, to the final lateral size of the component after thermomechanically processing the component;

wherein the thermomechanically processed Pd—In alloy has a bending stress measured with a three-point bending test, according to DIN EN ISO 9693 until breakage that is at least four time greater that the bending stress of as-cast the Pd—In alloy measured with the same three-point bending test.

2 . The component according to claim 1 ,

wherein the Pd—In alloy comprises between 1 and 10 wt % silver (Ag) or between 0.1 and 5 wt % aluminum (AI).

3 . The method according to claim 1 ,

wherein the Pd—In alloy comprises between 0.5 and 2 wt % Al and has a hardness HV1 between 220 and 320 HV1, or between 1.5 and 5 wt % Al and has a hardness HV1 above 280 HV1;

wherein hardness HV1 is measured with a load of 1 kg (9,81 N) using the measurement method defined in ISO 6507.

4 . The method according to claim 1 ,

wherein the Pd—In alloy comprises between 0.1% and 2% wt % Ru;

wherein the Pd—In alloy has grain size between 20 μm and 100 μm;

wherein the grain size is measured using optical microscopy and scanning electron microscopy (SEM) measurements of metallographic cross sections.

5 . The method according to claim 1 ,

wherein the Pd—In alloy comprises between 0.1% and 0.5% wt % Ru.

6 . The method according to claim 1 ,

wherein the Pd—In alloy comprising between 49.2% and 52.2% wt Pd, 46.2 and 50.5% wt In, between 0 and 1.42% wt Al, between 0 and 0.49% wt Ru, and a maximum of 1.5 wt % of other elements has a color in the CIELAB color space of L* between 73 and 75, a* between 9.4 and 9.8, and b* between 9 and 10.5;

wherein color was measured by using the CIE Standard Illuminant D65 and a 10° observer on metallographically polished sample of the component.

7 . The method according to claim 1 ,

wherein the Pd—In alloy is a Pd500 alloy.

8 . The method according to claim 1 ,

wherein the hot-pressed alloy is extruded by passing it through a die such as to form a wire having a diameter between 1 and 5 mm.

9 . The method according to claim 1 ,

wherein the hot-pressing step is performed at controlled deformation rate of 0.1 to 10 mm/h, and more specifically 0.5 to 2 mm/h.

10 . The method according to claim 1 ,

wherein the component is a watch component or part of a watch component.

11 . The method according to claim 1 ,

wherein the component is a component or part of a component for medical, for jewelry, or decorative applications.