新型含氟涂层在镀锡板上的抗腐蚀性能及机理

Corrosion Resistance Evaluation and Mechanism Analysis of New Fluoride-Containing Coating on Tinplate Sheets

硅烷改性含氟乳液用于金属表面处理时环保,且工艺简单、成本低廉,但目前研究较少。以含氟乳液和γ-(2,3-环氧丙氧基)丙基三甲氧基硅烷(KH560)为主成膜物质,同时添加无机钛、锆金属盐,制备新型含氟钝化液,并对镀锡板进行钝化处理。通过纳米粒度仪和红外光谱仪对含氟乳液进行表征,采用电化学、附着力、抗硫性、中性盐雾试验和原子力显微镜等测试方法对镀锡板表面涂层的性能进行测试,并探讨了其钝化机理。结果表明:含氟乳液的平均粒径为59.68 nm,稳定性良好,氟单体参加了反应;含氟镀锡钝化板的耐蚀性相对于空白板的明显提高,其耐蚀效果与成品有铬镀锡板相当,附着力达到标准1级,抗硫性优于成品有铬镀锡板,涂层表面趋于致密平整。

The main film was formed from fluorine-containing emulsion and 3-glycidoxypropyltrimethoxysilane （KH560） , and then inorganic metal salts of titanium and zirconium were added to obtain the new type of fluoridecontaining passivation solution. Subsequently, the tinplate sheets were treated by passivation. The fluoride-containing solution was characterized by nano particle size analyzer and infrared spectrometer, and the properties of the surface coating on tinplate sheets were tested by the electro-chemistry, adhesion, sulfide-stain resistance, neutral salt spray tests and atomic force microscope （AFM）. Furthermore, the passivation mechanism was discussed. Results showed that the average parti- cle diameter size of fluoride-containing solution was 59.68 nm, and the emulsion had good stability and fluoride-containing monomer participated in the reaction. The corrosion resistance of the fluoride-containing passivation tinplate was better than that of blank plate, equivalent to that of the finished product chromium plated tinplate. The adhesion force reached the primary standard, and the sulfide-stain resistance was better than that of the tinplate of chromate conversion film. Furthermore, the surface morphology became dense and uniform.