南海东部海域不锈钢紧固件的腐蚀失效分析

Analysis of Corrosion Failure of Stainless Steel Fasteners in Eastern of the South China Sea

【目的】为配合南海东部海区的海洋环境调查,研究该海区不锈钢紧固件发生的腐蚀现象。【方法】使用奥氏体不锈钢紧固件,利用海洋平台钢桩和不锈钢钢缆紧固相应的调查设备,通过一年的海试,检查该类不锈钢紧固件的腐蚀情况。【结果】不锈钢紧固件腐蚀严重,不同形状的材料腐蚀部位和程度不同。不锈钢的腐蚀主要表现为点蚀和隙缝腐蚀等局部腐蚀,严重时穿孔、断裂失效。【结论】建议在海洋金属结构中尽量使用同牌号同批次的同种金属材料,以确保材料电极电势相同,减小宏观电池的形成;若确实需要使用异种金属,必须对异种材料间进行电绝缘。

【Objective】To match marine environment investigation in the Eastern of the South China Sea,this article studied corrosion of stainless steel fasteners used for ocean dynamic environment monitoring system in the sea area.【Methods】Using austenite stainless steel fasteners,fastening equipment on steel pile of offshore platform and stainless steel cable,through sea trials a year,to check this type of corrosion of stainless steel fasteners.【Results】Serious corrosion effect of stainless steel fasteners was found,corrosion of materials of different shapes had different position and levels.Corrosion of stainless steels characterized by localized corrosion such as pitting and crevice corrosion,perforation and fracture failure severely.【Conclusion】To ensure the same electrode potential of the materials,and reduce the formation of the macro cell,it suggests that the grades and the batches of the same metal materials should be used in the marine metal structure;If you do need to use dissimilar metals,you must to electrical insulation between dissimilar materials.