COMPARISON BETWEEN CYCLIC DEFORMATION BEHAVIORS OF NON-ISOAXIAL COPPER TRICRYSTAL AND BICRVSTAL
非同轴取向Cu三晶体及双晶体的循环形变行为比较

The cyclic hardening and saturation behaviors of copper tricrystal and bicrystal were investigated by using successively increasing amplitude method. The results show that, to the inclined grain boundary bicrystal with single slip components, the cyclic stress strain curve (CSSC) ealsts a plateau or quasi-plateau region, while the CSSC of tricrystal shows no plateau.Observation of surface morphologies indicated that owing to the strain incompatibility of three grains, at lower strain amplitude the triple junction retards obviously the primary slip in grains and makes deformation near it smaller than that near bicrystal junction. The eastness of crack initiation at the same triple junction is closely related to loading direction.