中文摘要：

通过模拟油田井下低浓度H2s的工作环境，采用电化学技术研究35CrMo钢在不同pH的H2s溶液中的腐蚀行为，通过慢应变速率拉伸试验和U形弯试样浸泡试验研究35CrMo在不同pH和温度条件下的H2S介质中的应力腐蚀开裂行为与机理。结果表明，35CrMo钢在酸性H2S环境下SCC敏感性较高，随着介质的pH降低，35CrMo钢的应力腐蚀敏感性增加，腐蚀速率加快。pH降低能够较大地促进35CrMo钢阴极过程的进行，导致腐蚀速率和充氢电流密度均相应增大，从而导致局部阳极溶解作用和氢脆作用增大。在温度为15~90℃，35CrMo钢应力腐蚀敏感性不同，35℃和90℃条件下的应力腐蚀敏感性大。在酸性H2s环境下35CrMo钢的应力腐蚀机制是以氢脆为主，阳极溶解为辅的协同机制。

英文摘要：

Abstract： The combination of electrochemical corrosion technologies were performed to study corrosion of 35CrMo steel m H2S solution with various pH values by simulate the low concentrations of hydrogen sulfide environment of oilfield in the pit. Stress corrosion cracking（SCC） of 35CrMo steel in acidic hydrogen sulfide solutions with various pH values and temperature was investigated by U-bent specimen immersing test and slow strain rate tensile test. It is shown that 35CrMo steel exhibits a high susceptibility to SCC in acidic hydrogen sulfide solutions. The susceptibility and corrosion increases by decreasing the pH value of the solution. The susceptibility varied seriously with the change of pH value. The decrease of pH would accelerate the cathodic process greatly, leading to the increase of corrosion rate and hydrogen charging current density, resulting the local anodic dissolution and hydrogen embrittlement effect more significant. The different susceptibility to SCC of 35CrMo steel in 15-90 °C, Maximum susceptibility in 35 °C and 90 °C. The SCC mechanism of 35CrMo steel is hydrogen embrittlement（HE） mainly and combination of anodic dissolution（AD） in acidic hydrogen sulfide solutions.