Al-Zn热浸镀层在H_2S-NaCl-H_2O体系中的腐蚀行为

CORROSION BEHAVIOR OF HOT-DIP 55%Al-Zn ALLOY COATING IN H_2S-NaCl-H_2O SYSTEM

采用表面钝化助镀法进行热浸镀 ,获得了 55%Al -Zn镀层 .研究了溶液温度、H2 S浓度、NaCl浓度、pH值及试验时间对 55%Al-Zn镀层在H2 S -NaCl-H2 O体系中的腐蚀行为 .分析了镀层腐蚀前后的表面组织形貌及腐蚀产物 ,阐述了镀层的腐蚀机理 .结果表明 ,55%Al-Zn镀层具有Zn镀层的电化学保护作用 ,其耐蚀性是镀锌钢的 2～ 3倍 ,是碳钢Q2 35的 10～ 11倍 .

Fluxing in aqueous solution containing passivator and hot-dipping techniques were employed to prepare 55%Al-Zn alloy coating on carbon steel Q235.Effect of temperature,H 2S content,NaCl concentration,pH value and immersion time on corrosion behavior of hot-dip 55%Al-Zn alloy coating in H 2S-NaCl-H 2O system were studied.Surface morphology of this coating before and after corrosion was observed.The corrosion mechanism of 55%Al-Zn alloy coating in H 2S-NaCl-H 2O system was illuminated.Results showed that 55%Al-Zn alloy coating had the same ability as galvanized coating to protect the steel,and was 2～3 times corrosion resistant than galvanized coating ,10～11 times corrosion resistant than carbon steel Q235.