Stress Corrosion Cracking Susceptibility of Duplex Stainless Steels and Their Welds in Simulated Cooking Environments

Abstract

Abstract Stress corrosion cracking susceptibility (SCC) of the austenitic-ferritic stainless steels, i.e. duplex steels EN1.4462 (UNS S31803), EN1.4362 (UNS S32304) and EN1.4410 (UNS S32750) and their welds, which replicated weld structures in real digesters, have been examined in simulated kraft cooking environments. The effect of macro and micro stress state, phase ratio (ferrite content), liquor temperature and sulphidity on SCC has been clarified on the base steel grades and their welds. Guidelines to prevent SCC in digesters are presented.