Grain orientation dependence of lattice strains and intergranular damage rates in polycrystals under cyclic loading

Neutron diffraction experiments show that lattice strains in polycrystals under cyclic loading critically depend on the crystallographic orientations of diffracted grains, which can be explained by our crystal plasticity simulations and a micromechanical analysis based on slip anisotropy and the Taylor model. Experiments also show that the residual lattice strains gradually vanish with increasing number of fully reversed loading cycles. The corresponding decay rate correlates quantitatively with the grain-orientation-dependent total cumulative slip strain and qualitatively with grain boundary damage processes.