Powder metallurgy fabrication of palladium contact alloys

Abstract

The authors have combined some novel processing approaches to synthesize a high-performance material using powder metallurgy. A basic Pd-Ag-Cu composition was modified with metalloid additions to attain a fine grain size in combination with rapid solidification techniques. The internal grain structure was ideal for supersolidus sintering, having a dendritic arm spacing on the order of 1 mu m. The result is a fully dense alloy with attractive properties for electrical contact applications, including good conductivity, strength, wear, and corrosion resistance, comparable to or better than traditionally formed palladium-gold-silver-copper alloys. The addition of metalloids to the basic ternary system optimizes properties such as hardness and aids sinterability; yet the alloy can be fabricated without additional expense.<>