免水洗常温锰系磷化膜的制备与性能

Preparation and Properties of Room Temperature Washing-Free Mn Phosphate Film

将Q235钢试片在磷酸二氢锰、硝酸锰、钼酸钠、氟硼酸钠等组成的锰系磷化液中常温磷化后,自然干燥3h,制备了免水洗的彩色锰系磷化膜。考察了磷化液pH、磷化时间、磷化温度等工艺参数对磷化膜耐腐蚀性能的影响,用SEM及EDS分析了磷化膜的形貌和组成。结果表明,在磷化液pH为2.3-3.1、磷化温度5-40℃下浸渍磷化5-12min,可生成均匀、致密的彩色锰系磷化膜,其在质量分数3%氯化钠溶液中的耐腐蚀时间〉90min。喷涂铁红环氧底漆后,漆膜耐冲击性能达50cm,漆膜的附着力为1级。

A washing-free colourful manganese phosphate film was prepared on the surface of Q235 steel specimen at room temperature in manganese phosphate solution containing manganese dihydrogen phosphate,manganese nitrate,sodium molybdate,sodium fluoborate by phosphating and then natural drying for 3hours.The effect of pH value of phosphating solution,phosphating time,phosphating temperature on the properties of phosphating films were investigated.The morphology and composition of phosphating film were analysized through SEM and EDS.The results show that continuous and compact phosphate film was generated when the specimen was phosphated for 5-12min at 5-40 ℃in phosphating solution with pH value of 2.3-3.1.This film can resist the corrosion of 3wt%sodium chloride solution for over 90 minutes.The paint film sprayed with iron-red epoxy primer possessed impact resistance of 50 cm and adhesion force of 1grade.