Fatigue Design Curves for Domestic Recctor Pressure Vessel Steel in Primary Water

The effects of environment factors such as S content, stain rate, temperature and dissolved oxygen on the corrosion fatigue behavior of steels for reactor pressure vessel (RPV) in high temperature and high pressure water are reviewed. The difference of existing fatigue design models involving environmental factors is discussed also. The fatigue design curve of a domestic made low-alloy RPV steel was calculated by using statistical model (ANL model), fatigue correction factor model (EFD model) and a new model proposed (Wu model). A comparison of the calculated data and ASME fatigue design code was made. The results show that ANL model, EFD model and Wu model were relatively conservative when the stain amplitude was higher than 0.15%, while ASME fatigue design code was more conservative if the stain amplitude was less than 0.15%.