316L奥氏体不锈钢在高温水中的应力腐蚀

Stress Corrosion of Austenitic Stainless Steel 316L in High Temperature Water

为了得到裂纹尖端应力强度因子(K)、塑性变形量及水化学对316L奥氏体不锈钢在核电厂高温高压水中应力腐蚀开裂(SCC)的影响规律,采用dK/dt和dK/da两种不同的降K方式,在含氧与含氢高温水中,研究了冷变形316L不锈钢应力腐蚀裂纹扩展速率(CGR)与K值的关系。结果表明:在高变形量和苛刻的腐蚀环境条件下,316L不锈钢的应力腐蚀CGR对K值的依赖性降低;同时,降K加载过程得到的CGR比恒K加载时的低。

In order to get the effects of stress intensity factor at crack tip（K）,plastic deformation and hydrochemistry on the stress corrosion cracking（SCC）of austenitic stainless steel 316 Lin high temperature and pressure water of nuclear power plant,the relationship between stress corrosion crack growth rate（CGR）and K value of cold deformed 316 L stainless steel in high temperature water containing oxygen and hydrogen were investigated using two K decreasing methods of dK/dt and dK/da.The results show that in high deformation and harsh corrosive environment,the dependence of stress corrosion CGR on the K value of 316 L stainless steel decreased.At the same time,the CGR tested in the descending Kloading process was lower than that tested in the constant Kloading process.