热浸镀Zn-Al-Mg镀层在模拟湿热海洋大气环境中的腐蚀行为研究
Corrosion Behavior of Hot-dip Zn-Al-Mg Coating Exposed to a Simulated Hot and Humid Marine Atmosphere
顾天真 1刘雨薇 2彭灿 1张鹏 3王振尧 2汪川 2孙力3
作者信息
- 1. 中国科学院金属研究所,沈阳 110016;中国科学技术大学 材料科学与工程学院,沈阳 110016;辽宁沈阳土壤大气环境材料腐蚀国家野外科学观测研究站,沈阳 110016
- 2. 中国科学院金属研究所,沈阳 110016;辽宁沈阳土壤大气环境材料腐蚀国家野外科学观测研究站,沈阳 110016
- 3. 河钢集团钢研总院,石家庄 050023
- 折叠
摘要
目的 为详细研究热浸镀 Zn-Al-Mg 镀层在模拟湿热海洋大气下的腐蚀行为及作用机理,同时为热浸镀Zn-Al-Mg镀层在湿热海洋大气环境中服役提供数据参考.方法 采用腐蚀失重、XRD、SEM、电化学等测试方法对热浸镀 Zn-Al-Mg 镀层在模拟湿热海洋大气环境下的腐蚀行为进行研究.结果 腐蚀产物主要由Zn5(OH)8Cl2·H2O 组成,腐蚀一段时间后,发现少量 ZnO、Zn5(OH)6CO3,腐蚀产物具有与锌腐蚀类似的层状结构,1 848 h呈"三明治"型,相比于上下两层暗色物质,中层亮色腐蚀产物富集更多的Cl元素.热浸镀Zn-Al-Mg镀层腐蚀速率大体随时间延长呈上升趋势,只在672～840 h腐蚀速率下降,对比镀锌在模拟环境和锌在湿热大气环境中的腐蚀,热浸镀Zn-Al-Mg镀层在模拟湿热海洋大气中表现出较好的耐蚀性.结论 热浸镀Zn-Al-Mg镀层在模拟湿热海洋大气下腐蚀产物演变与腐蚀过程中Mg的参与有关.腐蚀 672～840 h阶段腐蚀速率下降的原因与腐蚀产物中 ZnO 的减少和Zn5(OH)8Cl2·H2O 占比增加有关.对比镀锌在模拟环境和锌在湿热大气环境中的腐蚀,预测热浸镀Zn-Al-Mg镀层在严酷湿热海洋大气中仍具有较高的耐蚀性,可以优先考虑作为湿热海洋环境的建设用材.
Abstract
The work aims to explore the corrosion behavior and mechanism of hot-dip Zn-Al-Mg coatings in a hot and humid marine atmosphere and provide data references for hot-dip Zn-Al-Mg coatings serving in the hot and humid marine atmosphere.The corrosion behavior of the hot-dip Zn-Al-Mg coating in a simulated hot and humid marine atmosphere was analyzed by corrosion weight loss,X-ray diffraction(XRD),scanning electron microscopy(SEM),electrochemical impedance spectroscopy(EIS)and other test methods.The results showed that the corrosion product was mainly composed of Zn5(OH)8Cl2·H2O.After a period of corrosion,a small amount of ZnO and Zn5(OH)6CO3 were found.The corrosion product evolution was related to the participation of Mg in the corrosion process.The corrosion product had a lamellar structure,which was like a"sandwich"at 1 848 h.Compared with the upper and lower layers of dark substances,the bright-colored corrosion product in the middle layer had more Cl elements concentration.The corrosion rate of the hot-dip Zn-Al-Mg coating generally increased with time,and only dropped sharply in the stage of 672-840 h.Comparison of galvanized coatings corrosion in a simulated hot and humid marine environment and zinc corrosion in a hot and humid outdoor marine atmospheric environment showed that the hot-dip Zn-Al-Mg coating had high corrosion resistance in the simulated hot and humid marine atmosphere environment.The evolution of corrosion products of the hot dip Zn-Al-Mg coating in a simulated hot and humid Marine atmosphere is related to Mg in the corrosion process.The reason for the decrease of corrosion rate at 672-840 h is related to the decrease of ZnO and the increase of Zn5(OH)8Cl2·H2O in corrosion products.It is predicted that the hot-dip Zn-Al-Mg coating still has high corrosion resistance in the hot and humid harsh marine atmosphere,and it can be given priority as a construction material for hot and humid marine atmosphere environment.
关键词
热浸镀Zn-Al-Mg镀层/湿热海洋大气/大气腐蚀/质量损失/腐蚀产物结构Key words
hot-dip Zn-Al-Mg coating/hot and humid marine atmosphere/atmospheric corrosion/mass loss/corrosion products structure引用本文复制引用
基金项目
河北省自然科学基金(E2021318006)
出版年
2024
国家科技期刊平台
NSTL
维普
万方数据