Study of Nanoscale Wear of SiC/Al Nanocomposites Using Molecular Dynamics Simulations

Abstract: In this work, molecular dynamics simulations are performed to investigate the nanoscale wear behavior of SiC particle-reinforced aluminum matrix composites (SiC/Al NCs) through nanoscratching using a spherical diamond indenter. A series of simulations are conducted to explore the effects of scratching depth, scratching speed, temperature, indenter size, and particle size during the nanoscratching process. We find the dislocation strengthening in the nanoscratching of SiC/Al NCs. It is also found that the frictional force and normal force increase with the increase of scratching depth, indenter size, and nanoparticle size. Moreover, the friction coefficient increases with the scratching depth. However, the friction coefficient declines with the increase of indenter size and nanoparticle size. Furthermore, for a larger scratching speed, the frictional force becomes smaller, while the normal force becomes larger, which is mainly determined by the competition between strain rate hardening and thermal softening. We also find that both the frictional force and normal force become smaller for a higher temperature resulting from thermal softening effect. The insights into the nanoscale wear properties of SiC/Al NCs lay a foundation for the wide applications of SiC/Al NCs. Graphical Abstract: [Figure not available: see fulltext.]