Modeling abrasive wear of homogeneous and heterogeneous materials

A micro-scale dynamic approach was recently proposed to simulate wear of materials. The model was developed based on fundamental physical laws without employing empirical equations or tribological rules. 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 wear, a lattice site may move under the influence of external force and the interaction between the site and its adjacent sites, which depends on the mechanical properties of the material, such as the elastic modulus, yield strength and work-hardening. The movement and trajectory of lattice sites during wear were determined using Newton's law of motion. A bond can be broken when the total accumulated plastic strain exceeds the fracture strain. A site or a cluster of sites is worn away if all bonds connecting the site or the cluster to its neighbors are broken. The model can provide information on the strain distribution in a contact region, consistent with finite element analysis. This model was applied to single-phase and composite materials abraded under dry sand/rubber wheel abrasion testing condition. Good agreement between the modeling and experiments was found.