| Abstract: | A generic model for frictional forces between two monoatomic crystals is investigated by molecular dynamics simulations. Two solids, each composed of several atomic layers, are brought into contact and moved against each other. The mechanisms that lead to finite pinning (static friction) forces are analyzed by varying the geometry, the interfacial interaction, and the externally applied force. Material transfer leading to welded junctions is seen to be responsible for friction between strongly adhering surfaces. Chemically passivated surfaces pin if they deform plastically. In no region of the model's parameter range can finite frictional forces be attributed to multistable elasticity. Such wearless pinning mechanisms play the predominant role in Frenkel–Kontorova and Tomlinson models. In the parameter range where pinning is observed, externally driven sliding induces wear at the interface. |
