冷变形316L不锈钢在高温高压水中的应力腐蚀

Stress corrosion cracking of cold worked 316L stainless steel in high temperature and high pressure pure water

采用恒应力强度因子K=33 MPa·m1/2的加载方法,利用直流电压降方法在线监测核辅管道316L不锈钢在高纯水中应力腐蚀裂纹扩展速率.对比200、250、280和325℃温度下,氩气除氧和含有2 mg·L-1溶解氧的水化学环境中材料的裂纹扩展速率发现:溶解氧为2 mg·L-1时的裂纹扩展速率明显比氩气除氧时的裂纹扩展速率高.氩气除氧时,裂纹扩展速率在250℃时有一个最高点;溶解氧为2 mg·L-1的条件下,裂纹扩展速率随温度的升高而升高.

The stress corrosion cracking growth behavior of 316L stainless steel, which is used as nuclear auxiliary pipelines, was continuously monitored by a direct current potential drop method under a constant stress intensity factor K of 33 MPa. m1/2. By comparing the cracking behavior of this material at 200, 250, 280 and 325 ℃ in 2 mg. L- 1 oxygenated water and deoxygenated water, we found that the crack growth rate is faster in the oxygenated water than in the deoxygenated water. Experimental results also show that there is a peak of the crack growth rate of this material in the deoxygenated water at 250 ℃, while the crack growth rate increases with the rise of temperature in the oxygenated water.