Effects of loading factors on environmental fatigue behavior of low-alloy pressure vessel steels in simulated BWR water

Low cycle fatigue resistance of low-alloy pressure vessel steels was investigated in simulated boiling water reactor (BWR) water. Much attention was paid to the effects of loading factors on fatigue life and environmentally assisted cracking (EAC) behavior, in which strain rate, strain waveform and strain amplitude were taken into account. The fatigue resistance and EAC behavior of the steels in simulated BWR water were found to be closely dependent on the strain rate, strain waveform and strain amplitude applied. The above fatigue behavior may be attributed to loading-factor-induced change in dominant EAC processes in high temperature water environments. Related EAC mechanisms are also discussed.