An asperity deformation model for the sliding cylinder problem : theoretical and experimental investigations

Abstract

Statistical analysis shows that the main reason for the failure of machines is not breakage but wear of the moving parts resulting from rubbing stress. Although the laws of friction are fairly well substantiated, there are still no satisfactory quantitative laws of wear. However, significant progress has been made in calculating how asperity contacts strain a wearing surface and in estimating how this may relate to wear rates. Among many attempts to develop quantitative models, the rigid plastic approach neglects elastic effects and allows slipline field theory to be used. Combining this with a damage rule, wear rates can be predicted from the strain calculations and the mechanical properties of the wearing material. In this theory, the hard asperity is represented as a rigid wedge, which is a limitation. Real asperities are more likely to have rounded tips and a more realistic approach is to model them with cylinders.