某码头钢板仓镀锌件腐蚀原因分析

Corrosion Reason Analysis on Galvanized Parts of Steel Plate Barn in a Port

某码头钢板仓镀锌件发生腐蚀生锈现象,通过现场调查对镀锌件的腐蚀形态进行分析发现,钢板仓镀锌件的腐蚀主要有3种形态。采用宏观分析、镀锌层质量试验以及腐蚀产物能谱分析等方法对镀锌件的腐蚀原因进行了分析。结果表明:钢板仓镀锌件发生腐蚀与镀锌层质量无关,钢板仓镀锌件发生腐蚀主要是由于钢板仓所在码头环境腐蚀性介质含量较高,镀锌层与切口处的钢铁形成了电偶腐蚀电池,以及镀锌件与地面或混凝土支座接触部位形成了氧浓差腐蚀电池所致。

Corrosion occurred on the surface of galvanized steel barn in a port,and three types of corrosion were found by the realty investigation.Corrosion reasons were analyzed by macro examination,zinc mass test and EDS.The results show that the zinc mass satisfied the requirement of design and had no relation with the corrosion.The main corrosion reason for the galvanized steel plate barn were in the high concentration of corrosive medium of the port environment,couple corrosion cell formed between zinc coating and the cutting edge,and the oxygen concentration different cell formed in the crevice between the galvanized parts and the ground or concrete.