【摘要】 采用动电位极化曲线测试法研究了温度、通气条件和pH值对X70管线钢在NS4溶液和0.5 mol/LNa2CO3+1 mol/L NaHCO3溶液中的电化学极化行为的影响,并用慢应变速率试验(SSRT)研究了X70管线钢在这些溶液中的应力腐蚀破裂(SCC)敏感性。结果表明,X70管线钢在NS4溶液中不出现活化—钝化转变区,随外加电位负移,SCC敏感性增加,表现出氢致破裂(HIC)的特征;在0.5 mol/L Na2CO3+1 mol/L NaHCO3高pH值溶液中出现活化—钝化转变区,在阴极极化区,也表现出氢致破裂(HIC)的特征,但在阳极极化区,发生的是阳极溶解型应力腐蚀破裂(ADSCC)。更多还原

【Abstract】 The influence of temperature,aerated condition and pH value on the electrochemical behavior and stress corrosion cracking（SCC） susceptibility of X70 pipeline steel in NS4 solution and 0.5 mol/L Na₂CO₃+1 mol/L NaHCO₃ solution was investigated using potentiodynamic polarization measurements and slow strain rate tests（SSRT）.In NS4 solution,active-passive transition behavior did not appear and SCC susceptibility increased with the negative movement of applied potential,indicating character of hydrogen induced cracking（HIC）.In 0.5 mol/L Na₂CO₃+1 mol/L NaHCO₃ solution,active-passive transition behavior was found in the potentiodynamic polarization curves,character of hydrogen induced cracking（HIC） was shown in cathodic polarization region and anodic dissolution SCC（ADSCC） occurred in anodic polarization region.更多还原