THEORY OF ENERGY-DISSIPATION IN SLIDING CRYSTAL-SURFACES AT NONZERO TEMPERATURE

Previous zero-temperature model studies of friction in a crystal undergoing plastic shear are extended to nonzero temperatures. For the case of a commensurate interface and most incommensurate interfaces without defects, thermal effects on the force of friction are found to be small. For the nearly commensurate case, however, it is argued that the force of friction should increase with increase in temperature. For the case of a commensurate interface with sliding taking place by the motion of dislocations, it is found that at temperature T small compared to the Debye temperature, thermal effects will be small, but as T becomes comparable to the Debye temperature, thermal effects dominate the force of friction.