Fatigue Crack Growth Behavior of Four Structural Alloys in High Temperature High Purity Oxygenated Water

The fatigue crack growth behavior of four structural alloys was studied and the effects of high temperature (288°C), high purity oxygenated water, cycle frequency, and mean stress were evaluated. The results for carbon and low alloy steel show that while crack growth rates are affected by the water environment, modified ASME code procedures result in conservative predictions of growth. Often, higher crack growth rates are found for shallow cracks than for deep cracks. For stainless steels and Inconel the measured growth rates in water were similar to data obtained in air over the range of cycle frequencies studied.