A microscale dynamical model for wear simulation

摘要

A computational approach, the so-called Micro-Scale Dynamical Model (MSDM), was developed to simulate wear processes and to predict material performance during wear processes. In this model, a material system is discretized and represented using a discrete lattice. Each lattice site represents a small volume of the material. During a wear process, a lattice site can move under influences of external force and the interaction between the site and its adjacent sites. The interaction between a pair of sites is dependent on mechanical properties of the material, such as the elastic modulus, the yield stress, the tensile strength the ductility, and work-hardening. The motion and trajectory of a site are determined by Newton's law of motion. The strainbetween a pair of sites is recoverable if it is within the elastic region, otherwise a plastic strain is caused. When the plastic strain exceeds the critical strain for fracture, the bond between a pair of sites is broken. A site or a cluster of sites isworn away if all bonds that connect the site to adjacent sites are broken. Wear loss of a material is affected by the wear conditions, including external force, deformation rate, and properties of the abrasive. Preliminary simulation has demonstrated that this approach has a great capability for dynamically simulating wear processes and predicting material performance during these processes.