The lattice strain ratio in characterizing the grain-to-grain interaction effect and its specific insight on the plastic deformation of polycrystalline materials

It becomes complex when the single grain is embedded in a stretched polycrystal, due to the grain neighborhood effect, which can outweigh the lateral contraction/expansion of that grain itself. Here, we performed numerical simulations to elucidate such grain-to-grain interaction effects on the lattice strain behavior.

For individual grains in a polycrystal, pseudo Poisson’s ratio is defined. Ratios of Poisson’s ratio over pseudo Poisson’s ratio were employed to indicate the difference between the cases of the grain deformation with and without the constraint imposed from the neighboring grains. The high-stress spots and the sense of the stress components can be identified with a high possibility according to the proposed ratios.