304H弹簧钢丝及弹簧表面腐蚀的原因

Reason for Surface Corrosion of 304H Spring Steel Wire and Spring

304H弹簧钢丝及弹簧在室内放置一段时间后,其表面局部出现锈蚀现象,对锈蚀部位和未锈蚀部位进行微观形貌观察和化学成分分析,探讨了304H弹簧钢丝及弹簧锈蚀的原因。结果表明:304H弹簧钢丝及弹簧锈蚀部位的微观形貌正常,但锈蚀部位表面存在铜或锌元素;304H钢盘条在精整打包过程中被打包机横轴的铜元素污染,在拉丝过程中被拉丝轮表面的锌元素污染;在304H弹簧钢丝及弹簧表面存在水膜的情况下,铜或锌元素与基体固溶体形成电位差而发生电化学腐蚀,从而发生局部锈蚀。

After placement for a certain time in the room,the partial surface of 304H spring steel wire and spring rusted.The microscopic morphology of rusty part and unrusty part was observed,and the chemical composition was analyzed.The rusty cause of 304H spring steel wire and spring was discussed.The results show that the rusty part of 304H spring steel wire and spring had the normal microscopic morphology,but copper or zinc elements existed on the surface of the rusty part.The wire rod was polluted by copper element from baler shaft during finishing packaging,and was polluted by zinc element from drawing wheel surface during wire drawing.The potential difference was formed between copper or zinc elements and matrix solid solution,and electrochemical corrosion occurred on the surface of 304H spring steel wire and spring when a water film existed on the surface,resulting in the occurrence of partial rust.