Molecular dynamics study of wearless friction in sub-micrometer size mechanisms and actuators based on an atomistic simplified model

Frictional resistance accompanying steady sliding motion is studied systematically as a function of various experimental parameters by means of molecular dynamics simulation using a two-dimensional model. Exploration of universal features lying in wearless friction in mesoscopic systems revealed unique dependence of the frictional force on sliding velocity, applied load, and mean temperature. Atomistic origin of this dependence is discussed in terms of “size effect” on the basis of a hypothesis that the frictional power corresponds to the rate of energy dissipation via forced vibration and subsequent energy transfer between normal phonon modes due to anharmonicity of inter-particle potential.