Abstract
To develop constitutive equations for mechanical ratcheting at elevated temperature, it is useful to examine behaviors of subsequent yield surfaces. A computer controlled testing system for getting subsequent yield surfaces automatically with the biaxial extensometer for elevated temperature and the device of high frequency heating system have been established. The subsequent yield surfaces have been examined experimentally for the initially isotropic materials of SUS316FR stainless steel subjected to mechanical ratcheting under combined cyclic torsion and steady tension at elevated temperature. As the result, the experiments found rotation as well as translation and distortion of the subsequent yield surfaces during mechanical ratcheting. An anisotropic yield Criterion for mechanical ratcheting is newly proposed in this paper.
