US 12,305,306 B2
Coated round wire
Miew Wan Lo, Singapore (SG); Murali Sarangapani, Singapore (SG); and Yong Sheng Wang, Singapore (SG)
Assigned to Heraeus Materials Singapore Pte. Ltd., Singapore (SG)
Appl. No. 18/558,294
Filed by Heraeus Materials Singapore Pte. Ltd., Singapore (SG)
PCT Filed May 4, 2022, PCT No. PCT/SG2022/050275
§ 371(c)(1), (2) Date Oct. 31, 2023,
PCT Pub. No. WO2022/235219, PCT Pub. Date Nov. 10, 2022.
Claims priority of application No. 10202104654V (SG), filed on May 5, 2021.
Prior Publication US 2024/0368794 A1, Nov. 7, 2024
Int. Cl. C25D 5/12 (2006.01); B21C 1/02 (2006.01); C25D 5/50 (2006.01); C25D 7/06 (2006.01)
CPC C25D 5/12 (2013.01) [B21C 1/02 (2013.01); C25D 5/50 (2013.01); C25D 7/0607 (2013.01)] 15 Claims
 
1. A round wire comprising a wire core with a surface, the wire core having a coating layer superimposed on its surface, wherein the wire core itself is a silver-based wire core, wherein the coating layer is a double-layer comprised of a 1 to 100 nm thick inner layer of palladium or nickel and an adjacent 1 to 250 nm thick outer layer of gold, wherein the outer layer of gold exhibits at least one of the following intrinsic properties A1) and A2):
A1) the average grain size of the crystal grains in the outer layer of gold, measured in longitudinal direction, is in the range of from 0.1 to 0.8 μm;
A2) 60 to 100% of the crystal grains in the outer layer of gold are oriented in <100> direction, and 0 to 20% of the crystal grains in the outer layer of gold are oriented in <111> direction, each % with respect to the total number of crystal grains with orientation parallel to the drawing direction of the wire.