Atomistic wear in a single asperity sliding contact.

Abrasive wear of sharp silicon tips sliding distances of up to 750 m on a polymeric surface is studied using atomic force microscopy. The data cannot be explained by conventional macroscopic wear models. We present a new model in which the barrier for breaking an atomic bond is lowered by the frictional stress acting on the contact. Quantitative agreement is obtained between the model and wear data for all load forces and sliding distances studied.