Elemental change of cast Ag-Pd-Au-Cu alloy surface by selective dissolution treatment

Abstract

Surface composition of Ag-Pd-Au-Cu based alloy castings is different from that of bulk. It is consider that sulfuration resistance of castings depends on composition of the surface layer. It is easy to come to tarnish on high copper density. We tried reforming of the outer layer by selective dissolution treatment which decline Cu and Ag to improve sulfuration resistance.