A novel nanoscale wear model in gaseous environment coupling the interfacial-bond formation and gas adsorption

Accompanying by the advancement of nanotechnology, the understanding of the nanoscale wear behavior has always been a focus of interest. Through examining the interfacial bond interactions at the atomic scale profoundly, many theoretical models of nanoscale wear have been developed. Nonetheless, the previously proposed nanoscale wear models were all established under vacuum conditions thus cannot work in gaseous environments which are more common. Herein, we proposed an interfacial-bond-based non-empirical nanoscale wear model for the gaseous environment, by assuming that only the surface atoms unpassivated by gas adsorption reactions are capable of forming interfacial bonds. In order to verify the validity of the proposed nanoscale wear model, reactive molecular dynamics simulations of an amorphous carbon ball sliding against a disk were performed under hydrogen environment. The proposed nanoscale wear model demonstrated an accurate prediction of the number of interface bonds and the amount of wear during friction under various hydrogen pressures. This work opens a way to theoretically calculate the nanoscale wear in gaseous environments, and will contribute to the development of design principles for nanoscale wear reduction.