Influence of heat treatment on tribological behaviour of Ni–P autocatalytic coatings

Abstract

Pin on disc tests were performed on Ni–P coatings, as deposited and heat treated at 200, 300, and 400°C for 1 h, to study the influence of heat treatment on the friction coefficient and wear resistance of the coatings. X-ray diffraction studies indicate thermally induced structural changes, which increase the hardness and wear resistance of the coatings. Heat treatment at 400°C induces complete crystallisation of the ductile Ni–P matrix to Ni₃ P and Ni (fcc), which are responsible for the highest hardness and wear resistance. Scanning electron micrographs of the wear tracks of the coatings show that adhesive and abrasive wear are the wear mechanisms involved in the wear of Ni–P autocatalytic coatings under dry non-lubricated conditions.