Surface topography and properties of frictional contacts

Abstract

The influence of surface topography on contacting solids is considered. The rough surface model is suggested and is used for the calculation of some tribological contact characteristics. A rough surface is modelled by a set of asperities of regular shape (wedge, cone, cylindrical, spherical segment), of differing height. A simple height distribution function and asperity shape function are used. These functions may be integrated analytically in further calculations. The surface model is used for calculation of one of the main contact parameters - real contact pressure (or real contact area) and other principal contact parameters, such as deformation, number of contact spots, average spot area, average distance between contact spots and intercontact gap. It is shown how the above parameters may be used for the calculation of such operational contact characteristics as friction coefficient, wear rate and electrical and thermal resistance.