镀锌钢表面氟锆酸盐/十二烷基三甲基溴化铵转化膜制备与耐蚀性研究  

Preparation and Corrosion Resistance of Fluorozirconate/DTAB Conversion Coatings on Galvanized Steels Surface

作　　者：徐花兰 郭瑞光[1] 唐长斌[1] XU Hua-lan;GUO Rui-guang;TANG Chang-bin(Key Laboratory of Water,Environment and Ecology in North China,Ministry of Ecology,Xi’an University of Architecture and Technology,Xi’an 710055,China)

机构地区：[1]西安建筑科技大学西北水资源与环境生态教育部重点实验室,陕西西安710055

出　　处：《材料保护》2020年第12期49-54,71,共7页Materials Protection

基　　金：国家自然科学基金项目(20976143);无锡高新区科技领军人才创业项目(2017年)资助。

摘　　要：为开发耐蚀性强的镀锌钢表面无铬转化膜技术,通过单因素试验确定了镀锌钢表面制备复合转化膜氟锆酸盐/十二烷基三甲基溴化铵(DTAB)的最佳条件为:氟锆酸钾4 g/L,DTAB 2 g/L,温度35℃,pH值4.0~4.2,时间45 min。采用扫描电镜(SEM)、傅里叶变换红外光谱(FT-IR)、能谱仪(EDS)、中性盐雾(NSS)、极化曲线和电化学阻抗谱(EIS)对转化膜的形貌、结构、组成及耐蚀性能进行了分析表征。结果表明:转化膜由ZrF4、ZrO_(2)和DTAB组成,约9.2μm厚,膜层致密,使得镀锌钢的腐蚀电位增加了72 mV,腐蚀电流密度降低了1个数量级,中性盐雾时间超过96 h。In order to develop a chrome-free conversion coating technology on the surface of galvanized steel with high corrosion resistance,the optimum conditions for preparing composite conversion coating fluorozirconate/dodecyltrimethyl ammonium bromide(DTAB)were determined by single factor test.The optimum conditions were potassium fluorozirconate 4 g/L,DTAB 2 g/L,35℃,pH 4.0~4.2 and 45 min.The morphology,structure,composition and corrosion resistance of the coating were studied by scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FT-IR),energy dispersive spectroscopy(EDS),neutral salt spray(NSS)test,polarization curve and electrochemical impedance spectroscopy(EIS).Results showed that the dense coating with about 9.2μm were composed of ZrF4,ZrO_(2)and DTAB,which increased the corrosion potential of galvanized steel by 72 mV,reduced the corrosion current density by an order of magnitude and made its neutral salt spray time over 96 h.

关 键 词：镀锌钢 转化膜 氟锆酸盐 十二烷基三甲基溴化铵 耐蚀性 

分 类 号：TG174.4[金属学及工艺—金属表面处理]