含缺陷Q345R钢焊接接头在湿硫化氢环境下的慢应变速率应力腐蚀试验研究

The investigation of slow strain rate stress corrosion for Q345R welding joint containing defects in wet hydrogen sulfide

采用缺口棒状试样模拟焊接缺陷表面气孔,通过慢应变速率(SSRT)应力腐蚀试验研究含有该缺陷的Q345R钢焊接接头在湿硫化氢环境中的应力腐蚀行为.结果表明:缺陷试样在拉伸过程中,受到应力集中和硫化氢溶液的协同作用,断裂时间和延伸率较无缺口试样都有明显下降,应力腐蚀敏感性大于无缺陷试样.含缺陷试样在湿硫化氢环境下的应力腐蚀敏感性随硫化氢质量分数的增加而增加,质量分数为200×10-6 H2S环境下断口呈现明显的应力腐蚀断裂特征.

In this paper, slow strain rate test （SSRT） were applied to study the stress corrosion of Q345R steel welding joint containing surface pore defects in wet hydrogen sulfide where gap round bar specimens were employed to simulate welding defect pores. Results showed that the fracture time and elongation had obviously decreased since defect samples suffered from the stress concentration and H2S solution environment in process of stretching. The stress corrosion cracking （SCC） sensitivity is higher than without defect samples. The sensitivity of defect samples in wet H2S environment rised with the mass fraction of H2S increased. And the typical frficture of stress corrosion cracking can be observed in 200× 10^- 6 H2S environment.