Mechanisms of cyclic softening and cyclic creep in low carbon steel

In order to understand better the mechanism of cyclic softening, a low carbon annealed steel has been first prestrained and then cycled in load control with zero mean stress. Both mechanical results and transmission electron microscopy studies of the defect structures were explored. Cyclic softening and creep were observed to occur in parallel. A new softening parameter, based on the changes in plastic strain amplitude with cycling and designed...