Intergranular Corrosion Evaluation of Stainless Steels and Higher Alloys at the Savannah River Site

The Savannah River Site has, for more than fi fty years, evaluatedthe susceptibility of austenitic stainless steels and other corrosion-resistant alloys to intergranular corrosion prior to use incritical site applications, including radioactive waste processingenvironments. Screening of alloys for sensitization and the potentialfor intergranular corrosion in certain environments is criticalto avoiding corrosion-induced in-service failures. In radioactivesystems, the consequences of such failures can be more signifi -cant than similar failures in non-radioactive environments. EarlyDuPont experience in using nitric acid in chemical plants andat the Savannah River Site led to the development of several testprotocols that have been adopted in ASTM A262 and G28 standardsand can be used to screen materials for service in potentiallycorrosive environments. This paper provides an overview of theapproach used at the Savannah River Site to screen materials forintergranular corrosion susceptibility in order to minimize intergranularcorrosion in chemical and radioactive waste processingsystems.