高温水中氯离子对316L不锈钢应力腐蚀裂纹扩展速率的影响

Effect of Chloride Ion on Stress Corrosion Crack Growth Rate of 316L Stainless Steel in High Temperature Pure Water

本文采用直流电压降(DCPD)方法,使用恒K(K=27.5 MPa·m1/2)加载方式,在核电厂高温高压水环境中研究了氯离子对316L不锈钢的应力腐蚀裂纹扩展速率的影响。实验结果表明:在高温除氧水中,氯离子会加快316L不锈钢的应力腐蚀裂纹扩展速率,且当水中存在溶解氧时,氯离子对应力腐蚀裂纹扩展速率的影响更明显。

The effect of chloride ions on stress corrosion crack（SCC）growth rate of316 Lstainless steel（SS）was studied in high temperature pure water of nuclear power plant environment.The stress corrosion crack length was continuously monitored by direct current potential drop under constant K of 27.5 MPa·m1/2.The results show that Cl-accelerates SCC growth rate of 316 L SS in high temperature deoxygenated water.In addition,the effect of Cl-on SCC growth rate is more remarkable in the presence of dissolved oxygen（DO）in high temperature pure water.