MODELING OF RESIDUAL STRESS IN MICRO-GRINDING CONSIDERING TEXTURE EFFECT

Residual stress is an important mechanical property parameter and a key evaluation index of the surface integrity. Residual stress induced in micro-grinding is related to the process parameters, the wheel properties, and material microstructure. The micro-grinding process is distinct from the conventional grinding owing to size effect, and the crystal effect. Typically, the effects of crystallographic orientation (CO) on process behaviors are significant by influencing the flow stress of workpiece material due to the depth of cut is usually less than the average grain size. In this paper, a Taylor factor model is developed to estimate the effect of CO on the flow stress and plastic modulus of monocrystalline materials. The flow stress model takes into account strain, strain rate, temperature, and material microstructure including grain size, CO, and dislocation density. The plastic modulus of monocrystalline materials h is given as the function of hardness, strain, and microstructure. The analytical model of residual stress is proposed considering the effects of CO. The hybrid McDowell algorithm is used to predict the residual stress with the developed plastic modulus. Finally, the sensitivity analysis is carried out, with the result showing that the effect of CO on residual stress is significant.