Mechanism of Fatigue Crack Initiation in Austenitic Stainless Steels in LWR Environments

摘要: This paper examines the mechanism of fatigue crack initiation in austenitic stainless steels (SSs) light water reactor (LWR) coolant environments. The effects key material and loading variables, such as strain amplitude, rate, temperature, level dissolved oxygen water, heat treatment on lives wrought cast SSs air LWR environments have been evaluated. influence formation growth cracks polished smooth SS specimens is discussed. Crack length a function cycles was determined results indicate that decreased these are caused primarily by environment <200 {micro}m and, to lesser extent, enhanced rates longer cracks. A detailed metallographic examination test performed characterize fracture morphology. Exploratory tests were conducted enhance our understanding surface micropits or minor differences oxide initiation.