Crystalline misfit-angle implications for solid sliding

For the contact of two finite portions of interacting rigid crystalline surfaces, we compute the pinning energy barrier dependency on the misfit angle and contact area. This simple model allows us to investigate a broad contact-size and angular range, thus obtaining the statistical properties of the energy barriers opposing sliding for a single asperity. These data are used to generate the distribution of static frictional thresholds for the contact of polycrystals, as in dry or even lubricated friction. This distribution is used as the input of a master equation to predict the sliding properties of macroscopic contacts.

► The pinning energy barrier depends on the misfit angle and contact area. ► We compute this dependence for a idealized rigid model. ► We obtain a distribution of static frictional thresholds. ► It is used as input of a master-equation model for macroscopic surfaces in contact. ► Overall we predict a transition from stick-slip to smooth sliding.