Corrosion behavior of 13Cr stainless steel under stress and crevice in high pressure CO2/O2 environment

In this work, through the self-developed setup for in situ electrochemical tests, the corrosion behavior of 13Cr stainless steel under the combined effect of stress and crevice in high pressure CO2/O2 environment was investigated. The results show that 13Cr stainless steel presents a self-passivation state. Under the action of stress, the anodic dissolution process of steel inside crevice is expedited. There is a galvanic effect between the stressed steel inside crevice and the unstressed steel outside crevice. The applied stress reduces the induction stage of crevice corrosion and induces a larger galvanic current, i.e., the applied stress promotes the development of crevice corrosion. Meanwhile, adding 0.1 MPa O2 is conducive to forming a more stable passive film but causes a greater galvanic effect.