Stress corrosion cracking behavior of high-strength mooring-chain steel in the SO2-polluted coastal atmosphere

• 作者: Menghao Liu Zhiyong Liu Cuiwei Du Xiaoqin Zhan Xiaojia Yang Xiaogang Li
• 来源期刊: 矿物冶金与材料学报
• 年，卷（期）: 2022,（6）
• 页码范围: 1186-1196
• 页数: 11页
• 语种: 英文

摘要

21Cr2NiMo steel is widely used to stabilize offshore oil platforms; however, it suffers from stress-corrosion cracking (SCC). Herein, we studied the SCC behavior of 21Cr2NiMo steel in SO2-polluted coastal atmospheres. Electrochemical tests revealed that the addition of SO2 increased the corrosion current. Rust characterization showed that SO2 addition densified the corrosion products and promoted pitting. Further-more, slow strain rate tests demonstrated a high susceptibility to SCC in high SO2 contents. Fracture morphologies revealed that the stress-cor-rosion cracks initiated at corrosion pits and the crack propagation showed transgranular and intergranular cracking modes. In conclusion, SCC is mix-controlled by anodic dissolution and hydrogen embrittlement mechanisms.