钡盐改性清洁型常温锌锰系磷化液

Zn-Mn System Phosphating Solution at Room Temperature Improved by Baric Ion

Q235钢铁试片在磷酸、氧化锌、硝酸锰、钼酸铵、硝酸钡等组成的钡盐改性锌锰系磷化液中常温快速磷化后,自然干燥3 h以上,生成了免水洗的彩色磷化膜。用SEM和EDS对磷化膜进行形貌和元素含量分析。结果表明,免水洗的磷化膜由铁、锌、锰、钡的磷酸盐及少量的钼酸盐等组成,膜晶粒尺寸≤3μm,膜连续、致密,膜重约1.1 g/m2,耐3%的NaCl溶液腐蚀约2.5 h,喷涂铁红环氧底漆后附着力达到一级。

The Zn-Mn system phosphating solution was composed of H3 PO4, ZnO, Mn （NO3）2, Ba （NO3）2, （NH4）6MoTO24·4H2O and so on. The washing-free color phosphating film could be formed quickly in the phosphating system on Q235 steel after drying for more than 3 h at room temperature. The morphology and element contents of the film were analyzed by SEM and EDS, The results showed that the washing-free phosphating film was composed of phosphate of Fe, Zn, Mn and Ba and a little of molybdate. The crystalline size of phosphating film was smaller than or equal to 3μm, The phosphating film was continuous and compact with weightiness of 1. 1 g/m2 , and was not corroded in 3% NaCl solution for about 2. 5 h. Its adhesion force reached 1st grade after spraying epoxy resin with iron oxide red.