The Stress Intensity Factor Dependence of 304 Stainless Steel SCC growth in Deaerated Water

摘要

Stress corrosion crack growth rate (SCCGR) tests wereconducted on 304 stainless steel (SS) in hydrogendeaerated water to characterize the dependence with thestress intensity factor (K). Tests were performed on four304SS heats at 321 and 328°C at K levels that rangedfrom 22 to 89 Mpa√m. Two test strategies were utilizedto quantify the SCCGR K dependence. The majority ofautoclave tests were single or dual specimen tests inwhich multiple K levels were step wise investigated andSCCGRs were evaluated through in-situ direct currentelectrical potential drop. Single K level specimen testswere performed on one 304SS heat at K levels of 25, 51and 74 Mpa√m. Results showed power law SCCGR Kfunctionality with power law exponents which rangedfrom 0.9 to 3.0. The K functionality measured from thesingle condition tests was lower than those measured insingle specimen multiple K conditions tests. The 304SSSCCGR vs. K results, as well as the role of uncrackedligaments on electrical potential drop (EPD) crackgrowth rate measurements and crack openingdisplacement, are discussed.