Mapping the micro-abrasion resistance of WC/Co based coatings in aqueous conditions

摘要

Significant progress has been made in recent years on the study of micro-abrasion mechanisms of materials. Regimes of micro-abrasion have been proposed which identify whether the wear occurs either by a two-body or a three-body mechanism. Microabrasion maps have been constructed showing the variation in wear regime, as a function of applied load and sliding distance. There has, however, been little work carried out to date on the micro-abrasion of composite coatings in such conditions. Here, because the size of the contact zone of the abrasion event may approach that of the abradant and the reinforcement (both typically < 10 mum), the wear mechanism is complex. In such cases, the properties of the reinforcement and the matrix material of the coatings may have a significant effect on the overall wastage rate. In this study, the micro-abrasion resistance of a WC/Co tribomet coating was compared with mild steel and stainless steel in an aqueous medium. Micro-abrasion mechanism and wastage maps were constructed indicating the wear regimes in such conditions. Possible reasons for the variation of the boundaries of the maps for the coated material compared with the steels are outlined, with reference to the mechanical and chemical properties of the coated and uncoated materials. (C) 2003 Elsevier B.V. All rights reserved.