对海洋油气井用1Cr13不锈钢进行了慢应变速率试验,并结合扫描电镜分析研究了其在不同腐蚀环境中的应力腐蚀敏感性。通过回归分析软件, 建立了1Cr13不锈钢的应力腐蚀敏感指数与各参数之间关系的数学模型。结果表明: 1Cr13不锈钢在H2S体积分数小于0.17%, pH大于3的环境中有较好的抗应力腐蚀能力; 交互四次型回归方程可以较好地反映1Cr13不锈钢应力腐蚀敏感指数Iδ与pH、Cl-质量分数、温度和H2S体积分数等介质参数的关系, 并且H2S质量分数和温度对应力腐蚀敏感指数产生交互作用。

The stress corrosion sensitivity of offshore oil and gas well steel 1Cr13 was studied in different corrosion environments through the slow strain rate testing (SSRT) combined with SEM. Using the regression analysis software, the mathematics model between stress corrosion sensitivity index of 1Cr13 steel and every parameter was established. The results show that 1Cr13 stainless steel had good corrosion resistance when the concentration of H2S was less than 0.17vol%, and the pH was more than 3. The interaction four regression equation could reflect the relationship among the stress corrosion sensitivity index of 1Cr13 steel, pH value, mass concentration of Cl-, temperature and mass concentration of H2S, in addition the volume concentration of H2S and temperature produced interaction effect on stress corrosion sensitivity index.