氯化物溶液中敏化304不锈钢应力腐蚀开裂的临界电位

SCC CRITICAL POTENTIAL OF SENSITIZED TYPE 304 STAINLESS STEEL IN CHLORIDE SOLUTIONS

研究了氯化物浓度、溶液温度、应力及敏化程度对敏化３０４不锈钢在ＮａＣｌ水溶液中晶间型应力腐蚀开裂的影响．结果表明，材料的敏化程度、ＮａＣｌ浓度、溶液温度和应力对敏化３０４不锈钢的ＥＲ．ｓｃｃ有显著的影响．敏化３０４不锈钢的ＥＲ．ｓｃｃ低于ＥＲ．ＣＲＥＶ．应力腐蚀开裂发生在正于ＥＲ．ｓｃｃ的电位范围，而电位低于该值则免于发生应力腐蚀开裂．由此得知，ＥＲ．ｓｃｃ可适用于评价敏化不锈钢的应力腐蚀开裂敏感性．

The effects of various material and environmental factors on the intergranular stress corrosion cracking(IGSCC) susceptibility of sensitixed type 304 stainless steel in NaCl solutions were studied.The repassivation potential for SCC(ER.scc) strongly depends upon the degree of sensitization of the material,NaCl concentration,testing temperature and applied stress level for the sensitized specimens.ER.scc is more negative than repassivation potential for crevice corrosion ER.CREV The range of potential leading to cracking always stud from the level equal to ER.scc and errands to higher potential levels. But no cracking occurs at potenttials below ER.scc'The applicability of the ER.scc to evaluating the susceptibilityto SCC for the sensitized 304 stainless steel has been confirmed in this study.