Fatigue crack propagation in a low alloy steel in a de-aerated distilled water environment

Abstract

A study has been made of corrosion fatigue in a 0.5Cr0.5Mo0.25V low alloy steel in a de-aerated distilled water environment at various test temperatures, using the change of specimen compliance with fatigue crack growth as a method of monitoring the crack length. The fatigue crack growth rates and fracture surfaces are compared with those obtained in a dry argon reference environment. The corrosion fatigue is shown to be controlled by a thermally activated process, with an apparent activaton energy independent of the crack tip stress intensity. The percentage of intergranular failure is correlated with the increase in the fatigue crack growth rate due to the aqueous environment.