抄録
Single crystal plasticity based on a representative characteristic length is proposed and introduced into a homogenization approach based on finite element analyses, which are applied to characterization of yielding behavior, yield-point elongation and grain size strengthening. Here we assume that the gram boundary inhibits the plastic deformation and that the resistance effect can be described with the internal characteristic length in the proposed constitutive model. In this context, the characteristic length is given explicitly as the distance from the grain boundary. The feature of the approach is that the scale can be introduced explicitly into a representative volume element model as the distance from the grain boundary with the hardening character based on the accumulation of the dislocations. Using finite element analysis for periodic microstructure, the nonlinear grain-size dependency on yield strength is characterized, in which both Hall-Petch relationship at coarse grain region and non-Hall-Petch relationship at fine grain region are consistently reproduced.
