Elasto-plastic partial slip contact modeling of graded layers

Abstract

A calculation model is developed to solve elasto-plastic partial slip contact problems of graded layer-substrate systems. With the high dependence of contact stress on the local region near the contact spot, the graded layer-substrate system of interest is modeled as a homogeneous half-plane with an embedded, finitely long inclusion. Unlike the conventional finite element method, the elasto-plastic responses are solved within a considerably small region rather than an oversized truncated domain. The computational domain allows arbitrary distributions of elasto-plastic properties and is directly discretized without tedious separation and assembling skills. The resulting disturbance fields are calculated by the numerical equivalent inclusion method. Additionally, the plastic strain is determined via the return-mapping algorithm, and the generated residual responses are directly obtained based on the explicit theoretical solutions. The conjugate gradient method is utilized to solve surface tractions, and the induced elasto-plastic fields are calculated by the technique of fast Fourier transform. Some parametric studies are subsequently conducted based on the developed model to explore the effects of property inhomogeneity and friction coefficient on the elasto-plastic response.