Abstract
In this work, the plastic behaviours of polycrystalline metals in two typical examples of complex loading conditions are computationally analyzed by using a simplified mechanical model of polycrystal in the manner of a crystal plasticity type. The first example is a deformations along a strain path with a corner, and the second one is a so-called mechanical ratcheting deformation. The variations of microscopic stress in some single crystal components in the polycrystal model are discussed in detail, and then the relation between the macroscopic stress and microscopic stress is clarified. Especially, it is an important mechanism related with some macroscopic features of polycrystalline metals under such complex loading conditions observed in the experiments.
