Crystal plasticity simulation of polycrystalline aluminum and the effect of mesh refinement on mechanical responses

Plastic heterogeneities of polycrystalline aluminum during tensile test have been numerically investigated at grain level. Responses at several length scales are studied, including the overall stress, intergranular and intragranular stress-strain heterogeneities. Special attention is paid to the sensitivity of simulation with respect to the mesh refinement. The results show that, a coarse mesh containing about 500 grains is sufficient to predict the global stress-strain curve, with only one element per grain. About 5 elements per grain is enough to well describe the intergraunlar heterogeneities. However, at least 30 and 60 elements per grain should be used, in order to well describe the average deformation behavior of each grain and to capture most of the intragraunlar heterogeneities, respectively.