KINEMATIC HARDENING RULES FOR SIMULATION OF RATCHETTING BEHAVIOR

For simulating ratchetting behavior, the present authors formulated kinematic hardening rules on the assumption that each component of back stress, alpha(i), has a critical state for its dynamic recovery to be fully activated. These rules have a feature that only the projection of plastic strain rate to the direction of alpha(i) contributes to the dynamic recovery. They are thus in contrast with the previous rules in which the accumulated plastic strain rate enters into the dynamic recovery term. We compare the present and such previous rules by applying them to multixial and uniaxil ratchetting experiments of Modified 9Cr-1Mo steel at 550 degrees C.