Anisotropic yield criterion for polycrystalline metals using texture and crystal symmetries

An anisotropic yield criterion for polycrystalline metals which uses texture data and takes advantage of crystal symmetries is presented[ A linear transformation is developed to map an anisotropic yield surface for a polycrystal to an appropriate isotropic yield surface[ The transformation developed re~ects the symmetry of the material being modeled[ First\ the transformation is determined[ Then\ information regard! ing the orientation distribution "texture# of the crystals in a polycrystalline aggregate is used to determinevia averaging\ the transformation for the polycrystal[ The transformation\ along with appropriate isotropic yield surface\ provides a phenomenological approach to modeling yield\ yet accounts for microstructural texture[ The approach reduces to the Hill "0849# anisotropic plasticity theory under certain conditions[ The yield surfaces and R!values for various face!centered!cubic " fcc# polycrystalline textures are computed by this method[ Results compare favorably with those given by other theories\ and with experiment[ The method proves to have the computational e.ciency of phenomenological approaches to modeling yieldwhile e}ectively incorporating the physics of more complex crystallographic approaches