Fifty years of research on the wear of metals

Research on the wear of metals which took place over the past half century has brought new understanding and advanced major concepts of tribology. Such key work comprises a subset of a much larger body of published studies which simply report wear test results. The availability of new testing methods and instruments have made possible the detailed study of the microstructure, nanostructure, and compositions of contact surfaces. The classical work of the earlier decades concentrated on the mechanics of solid contact, understanding the true area of contact, asperity plasticity, and transfer during sliding. Wear science also witnessed the establishment of the conceptual groundwork for such things as the critical angle for maximum erosion rate by particles, the proportionality between hardness and abrasive wear rate, and the nature of slip and stick in fretting contact. Later decades brought forth instruments, like the scanning electron microscope and the atomic force microscope, which have provided fascinating insights and detailed information on surface structure. There have also been developments in computational modelling of wear by finite element methods, molecular dynamics, and fracture mechanics. Past trends in the study of various forms of metal wear and future trends and needs in wear research are discussed. (C) 1997 Elsevier Science Ltd.