免水洗锌钙系磷化膜的常温制备与表征

The Preparation and Characterization of Zn-Ca System Phosphating Film Without Washing at the Room Temperature

钢铁试片在以磷酸、氧化锌、硝酸钙、钼酸铵等参加成膜反应且产物为磷化膜、沉渣和易挥发物的材料组成的锌钙系磷化液中常温快速磷化,然后自然干燥2 h以上,生成了免水洗的彩色锌钙系磷化膜.通过扫描电镜(SEM)、电子能谱(XPS)、腐蚀、喷涂等测试手段对磷化膜进行表征.结果表明:免水洗的磷化膜,由Fe3+,Zn2+,Ca2+的磷酸盐及少量的钼酸盐等组成,膜晶粒尺寸≤2μm,膜连续、致密,膜重约1.2 g.m-2,耐3%的NaCl溶液腐蚀约2.5 h,喷涂铁红环氧底漆后检验涂层的附着力达一级,比传统工艺(磷化后水洗)形成的磷化膜质量更好.

The Zn-Ca system phosphating solution is composed of H3PO4, ZnO, Ca（NO3）2·4H2O, Ba（NO3）2, （NH4 ）6Mo7O24·4H2O and so on, which react with each other to produce phosphating film, sediment and volatile. The Zn- Ca system phosphating solution is fast occurred phosphating reaction on steel acted as matrix and then was dried for more than 2 h to produce eolour Zn-Ca System phosphating film. The phosphating film was characterized by means of SEM, XPS, rest, and smear. The results show that the phosphating film without washing is composed of phosphate with Fe^3＋ , Zn^2＋ and Ca^2＋ . The phosphating film, whose crystalline size is small than or equal to 2 pan, is series and thick with weightiness of 1.2 g·m^2. It bears corrupt of NaCI solution with 3% for about 2.5 h. The cling force of phosphating film, smeared by lacquer of epoxy resin antirust of iron oxide red, reaches stair, and the quality of the phosphating film is more than that of phosphating film prepared by traditional technology, i .e. washing after phosphating reaction.