Multiscale simulation of the compress behavior on single crystal copper microstructure based on quasicontinuum method

Based on quasicontinuum (QC) multiscale simulation method, a series of simulation models were set up for compressing rod-shaped microstructure of single crystal Cu. The effects of structural parameters on typical mechanics parameters were analyzed, such as elastic modulus, ultimate elastic stress, yield strength and Poisson's ratio. The mechanisms of crush and compressed deformation were also revealed according to the analysis of displacement, inner stress and strain energy. It can be shown that the size effects of elastic modulus, ultimate elastic stress and yield strength in compression of microstructure are more obvious than that in macro scale. However, the size effect of Poisson's ratio is not remarkable in the simulation results. The dimension change in one direction cannot influence the mechanics parameters greatly. Mechanical twins and dislocation contribute mainly to the compression behavior. Meanwhile, stress concentration can also be found in the inner partial area and the stain energy decreases instantly after the crush of rod-shaped microstructure.