海生物附著对钢板管椿腐蚀之影响

Influence of Marine Organisms upon Corrosion of Steel Piling Systems

为了解海生物对钢板管椿腐蚀之影响 ,将SS4 1金属试片浸渍于高雄港 #1 4码头水深 3m处及实验室人造海水中 .试验期间 ,以DC直流动电位极化曲线扫描与AC交流电阻抗分析现场量测各试片的瞬间腐蚀速率 .结果发现 :宏观地看 ,海生物在金属 (或锈层 )表面的附著可以减缓金属腐蚀 ,但从微观 (micro)的观点推论 ,海生物在金属表面的附著亦可以造成氧差或浓度差异电池 ,促成局部腐蚀 .此外 ,等效电路的模拟 ,有助于了解海生物附著对金属腐蚀的影响 ,即随浸渍时间的延长 ,金属表面因锈层增厚且趋于致密 ,以致锈层电阻增加 ;又因海生物种类不同 ,含水量不同 。

To study the influence of marine organisms upon corrosion of ASTM A36 steel piling sysems,specimens were immersed in both natural and synthetic seawater.Electrochemical techniques such as linear polarization resistance and electrochemical impedance scan(EIS) were applied to evaluate corrosion of the steel.The results indicated that attachment of marine organisms to form fouling layers on the steel surface reduced general corrosion,but localized corrosion occurred underneath marine organisms.An equivalent circuit model was established to simulate attachment of marine organisms upon carbon carbon steel surfaces.