Fretting wear characteristics of Ni/Cu multilayers electrodeposited on beryllium bronze substrate

Fretting test were carried out with a sphere-on-hat geometry to investigate the wear mechanisms of electrodeposited Cu/Ni multilayer films. The effect of the layer spacing of multilayer films on the fretting wear and friction coefficient of the specimens has also been studied in the fretting conditions. Scanning electron microscopy (SEM) and electron probe microanalyser (EPMA) were used to observe and analyze the morphology of the fretting surface and wear debris of the films. The results of the fretting experiments showed that the sublayer thickness of multilayer films had a significant influence on the fretting wear resistance of the Cu/Ni multilayer films. When the sublayer thickness was more than 60 nm, the fretting wear resistance of multilayer films was poor. However, the multilayer films with the < 60 nm sub-layer thickness have much better fretting wear resistance than the thick ones with the > 60 nm sub-layer thickness. The mechanism of fretting wear for multilayer films were adhesion and fatigue. Wear debris of fretting was small. The debris comprised largely of oxide particles. (C) 1998 Elsevier Science S.A.