Abstract：Using polycrystalline plasticity analytical method and considering that there were a great deal of anisotropy crystal grains in material point and that influence is coming from scale effect, stress and strain in material point were calculated adopting Taylor’s hypotheses in the paper. Hardening function of crystal slip taking scale effect into account and back stress that reflecting crystal’s directional hardening was introduced into the model, which can describe the mechanical behavior of a material, including scale effect of crystal grain under cyclic loads. The first author of the paper compiled a user material subroutine (VUMAT) in explicit arithmetic suitable for the interface of ABAQUS; it can be adopted to describe the cyclic plasticity behavior and size effect of polycrystalline metallic material under repetitive loading. The simulation of a material’s representative volume element which consists of a number of crystal grains was carried out, the results were confirmed reasonable in size effect for a polycrystal under cycle load.
2012, Vol. 33 
