Mechanisms of adhesion-initiated catastrophic wear: pure sliding

Understanding in the field of catastrophic wear is currently becoming well established. But serious incongruities may be found in the terminology in use in different countries that raise obstacles to effective translation and further work. There is a lack of conformity of standard definitions that reflects, at least in part, the wide diversity that has been found in the types of catastrophic wear and the mechanisms by which they occur. A number of attempts have been made since the earliest investigations to delineate them. In this paper, mechanisms of wear which can be identified as types of adhesion-initiated catastrophic wear (AICW) are investigated. A historical review of the past usage and observed mechanisms of seizure, scoring, scuffing, and galling, leads to tentative refinement of the definitions of these terms. Detailed study of their early stages of development and nucleation establishes close connections with (a) different modes of plastic deformation, and (b) competitive rates of formation and stripping of adsorbed oxide layers. New experimental data are presented and discussed for intensive strain-hardening of steels at low and high sliding speed and for electrical contact behaviour of soft/hard and hard/hard lubricated friction pairs. In preparing the paper, intensive use has been made of the tribological treasure trove that has accumulated in English and Russian.