#6-Wrought Clad Inlay Palladium-Nickel Contact Material Systems for Dry Circuit Applications from Materion Technical Materials
Abstract: Palladium based contact materials have been used successfully in telecommunications, computer and automotive dry circuit applications. Deleterious frictional polymer formation is prevented by coating palladium and palladium co-deposits with a gold surface layer. Nobility is maintained at lower cost when compared to gold over nickel at equivalent thickness.
Current electroplated systems include thick gold or a gold flash over palladium (Pd) and palladium-nickel (PdNi). The properties and performance characteristics of electroplated PdNi coatings are a function of:
- The palladium-nickel bath chemistry
- Plating manufacturing practice
- The ability to control the palladium-to-nickel ratio
In contrast, consistent and reproducible alloy chemistry is intrinsic to metallurgically processed materials. This Materion Technical Materials paper characterizes the properties of wrought PdNi contact materials. The bulk PdNi alloys exhibited hardness values (300 HV500, bend R/t ratios of less than 1.0, an average electrical resistivity of 21.5 ((-cm, excellent oxidation resistance and moderate chemical stability.
Wrought Clad Inlay Palladium-NickelDiffused gold (DG) and gold flash (GF) clad inlay PdNi materials demonstrated excellent thermal and chemical stability, and proved durable when cycled against plated hard gold. Both DG and GF clad inlay PdNi contact materials exhibited preferred performance attributes. Cost estimates for both wrought and electroplated systems are presented.