304不锈钢防盗罩锈蚀原因分析

Reason Analysis on Tarnishing of 304 Stainless Steel Anti-Theft Cover

某304不锈钢防盗罩安装一周后,部分管材表面出现严重锈蚀,采用宏观观察、金相检验、扫描电镜分析、能谱分析、化学成分分析、电化学腐蚀试验、模拟对比试验等方法,对锈蚀原因及机理进行了分析。结果表明:管材表面受到含氯酸性腐蚀物质侵蚀,材料的钝化层遭到破坏,发生了点腐蚀,并逐步发展为严重锈蚀。

After one week of installation,the surface of 304 stainless steel pipes of a anti-theft cover suffered serious tarnishing.In order to find out the tarnishing causes and mechanism,the pipe were analyzed by methods of macroscopic observation,metallographic examination,scanning electron microscope analysis,energy spectrum analysis,chemical composition analysis,electrochemical corrosion test and simulated contrast test.The results show that the surface of the pipe was corroded by chlorinated acid,which caused the passivation layer of material to be damaged and pitting corrosion,and it gradually developed to serious tarnishing.