SCC GROWTH RATE TESTING OF COLD WORKED STAINLESS STEEL IN HYDROGEN DEAERATED WATER

摘要

Stress corrosion cracking growth rate (SCCGR) tests have been conducted on cold worked stainless steel (SS) in high purity hydrogen deaerated water to characterize the SCCGR temperature, hydrogen concentration, and sensitization dependencies. Deaerated water (DW) test results showed that cold worked 304SS SCCGR generally followed an Arrhenius temperature functionality with an activation energy of 75 kJ/mol. Some 304SS heats, particularly at low levels of cold work, however, deviated from this Arrhenius temperature functionality and showed reduced SCCGR at elevated temperature (360°C). Results also showed a complex effect of sensitization heat treatment with sensitization heat treatment being detrimental at moderate temperatures (249°C) but beneficial at elevated temperature (360°C). Unlike nickel based alloys, 304SS SCCGR did not depend upon the coolant hydrogen concentration but was a function of the sulfur content.