A phenomenological model for frictional contact accounting for wear effects

A simple phenomenological model for frictional contact accounting for wear effects is proposed. The objective is the numerical simulation of the frictional behaviour of contacting bodies subjected to large sliding distances and variable normal pressures. Within the context of thermodynamics with internal variables, the friction coefficient is assumed to be a function of the density of frictional work resulting in a theory analogous to classical work hardening elastoplasticity. The technique for experimental identification of the proposed model, applied to sheet materials, is described and the material parameters for some steel sheets commonly used in industry are determined. The framework for the computer simulation of the model in large scale problems is based on a fully implicit finite-element scheme and the Newton-Raphson method. A robust algorithm based on an operator split method (elastic predictor-frictional sliding corrector) is used for numerical integration of the friction constitutive equations. The simulation of a series of sliding tests is carried out and the results are compared with experiments.