带锈钢材表面单宁酸–磷酸复合转化膜的防腐蚀性能  

Corrosion resistance of tannic–phosphoric acid composite film on rusty steel substrate

作　　者：屈中伟 李欣 杨鹏[2] 赵定义 

机构地区：[1]武汉科迪奥电力科技有限公司,湖北武汉430074 [2]武汉理工大学理学院,湖北武汉430070

出　　处：《电镀与涂饰》2015年第1期8-13,65,共6页Electroplating & Finishing

基　　金：国网科技项目"输变电设备防腐材料开发及应用关键技术研究"

摘　　要：对Q235钢片进行中性盐雾(NSS)腐蚀后再采用单宁酸–磷酸复合体系进行转化处理。研究了转化液组成和NSS时间对转化膜耐蚀性的影响,表征了单宁酸–磷酸复合转化膜的耐蚀性、表面形貌和组成,并探讨了转化膜的形成和作用机理。结果表明,单宁酸–磷酸复合转化可显著提高带锈钢材的耐蚀性,最佳的转化液组成为5 g/L单宁酸+15 g/L磷酸。单宁酸–磷酸复合转化膜为蓝灰色,主要由单宁酸铁螯合物和Fe PO4组成,表面平整、致密。Q235 steel plate was corroded by neutral salt spray （NSS） followed by conversion coating with a tannic- phosphoric acid composite system. The effects of conversion bath composition and NSS corrosion time on the corrosion resistance of conversion coating were studied. The corrosion resistance, surface morphology, and composition of tannic phosphoric acid composite conversion coating were characterized. The mechanism of formation and action of the composite conversion coating was discussed. The results showed that the tannic-phosphoric acid composite conversion can dramatically improve the corrosion resistance of rusty steel substrate. The optimal conversion bath comprises of 5 g/L tannic acid and 15 g/L phosphoric acid. The tannic-phosphoric acid composite conversion film is blue-gray, smooth, and compact, and mainly composed of ferric tannate chelate and FePO4.

关 键 词：带锈钢 单宁酸 磷酸 转化膜 耐蚀性 

分 类 号：TG178[金属学及工艺—金属表面处理] TG174.21[金属学及工艺—金属学]