STICK-SLIP DYNAMICS OF INTERFACIAL FRICTION

We investigate a model system which consists of a chain of particles t hat interact with two periodic potentials representing two confining p lates. one of which is externally driven. The model leads to a spectru m of rich behaviors in the motion of the top driven plate: stick-slip, intermittent kinetic regime characterized by force fluctuations, and two types of sliding above a critical driving velocity v(c). Similar b ehaviors are typical of a broad range of systems including thin sheare d liquids. The relaxation of the ''slip'' part between two ''stick'' e vents in the stick-slip time series may display more than one characte ristic time scale. The different relaxation times are shown to be rela ted ro a velocity-dependent effective frictional force felt by the dri ven plate. (C) 1998 Published by Elsevier Science B.V. All rights rese rved.