促进剂对钢铁常温磷化的影响及机理

采用锌系磷化工艺对钢铁表面进行防护,以提高钢铁表面耐蚀性及与涂层的结合力。以磷化膜外观及耐蚀性为考察指标,通过单因素实验考察了常温锌系磷化液中硝酸铜、柠檬酸、氟化钠、硝酸镍和钼酸钠5种促进剂对磷化的影响。结果表明,各促进剂对磷化膜外观及耐蚀性均有明显的促进作用,其适宜质量浓度为:0.08 g/L硝酸铜,2 g/L柠檬酸,1.2 g/L氟化钠,15 g/L硝酸镍,2 g/L钼酸钠,并探讨了促进剂的磷化作用机理。

Effect and Mechanism of Accelerator on Steel Phosphating at Room Temperature

Steel surface was protected by zinc phosphating technology,in order to improve the corrosion resistance of steel and the adhesion between the steel surface and coating.Regarding the appearance and corrosion resistance of the phosphate film as the index of evaluation,the influences of five kinds of accelerators such as cupric nitrate,citric acid,sodium fluoride,nickel nitrate and sodium molybdate on zinc phosphating of steel at room temperature were studied by single factor experiment.The results showed that every kind of accelerators had obvious promotion effect on the appearance and corrosion resistance of phosphating film.The suitable concentration was as follows:Cu (NO3) 2 0.08 g/L,C6H8O7 2 g/L,NaF 1.2g/L,Ni (NO3)2 15g/L,Na2MoO4 2g/L.The phosphating mechanism of the accelerator was also discussed.