Abstract
The crystal structure and properties of electrodeposited Pd-Ni-P alloy films were investigated. The alloy films obtained were made up of a Pd-Ni solid-solution phase and a Pd-Ni-P amorphous phase. With phosphorus codeposition, the films were found to undergo orientation transformations into the closed-packed facet of the fcc lattice and a decrease in the crystallite size of the Pd-Ni solid-solution phase. The hardness of the films increased with an increase in phosphorus content, reaching a maximum of over 1500Hv for alloys containing 60mol% Pd-32mol% Ni-8 mol% P after heat treatment at 350°C, and resulting in precipitation hardening of the Pd-Ni-P phase. The electric contact resistance of the films was less than 1.5mΩ at a load of 50g.
Based on these experimental results on hardness and electric contact resistance, it is suggested that electrodeposited Pd-Ni-P alloys may be used as an alternative to electrodeposited rhodium for high-load electrical contacts.
