摘要： 传统磷化处理工艺中,重金属盐的使用对环境造成了严重污染。文中从磷化液配方和磷化后封闭液配方两方面入手,摒弃有毒重金属的使用,开发了一种磷化膜晶粒细小、附着力强、耐冲击性强的金属表面绿色磷化处理技术。以X70管线钢为基材,进行磷化处理,并通过磷化膜形貌分析、CuSO₄点滴实验、综合性能对比、线性极化分析和电化学阻抗分析等方法研究了磷化处理效果。经过绿色磷化处理,X70管线钢的腐蚀电流从55.105 μA/cm²下降到35.719 μA/cm²,再经硅酸盐封闭处理后,腐蚀电流下降到0.043 μA/cm²;磷化未封闭的X70管线钢表面的磷化膜是存在大量孔隙的非致密膜,通过硅酸盐封闭后,磷化膜的致密程度大幅提高,电导率大幅降低,对金属基体有较好的腐蚀保护作用。

关键词: 磷化, 重金属, 绿色环保, 硅酸盐, 封闭

Abstract: The phosphating technique has been widely used for surface treatment of metal. As for the traditional phosphating treatment process, the use of heavy metal poses a great threat to the environment. A new environmental friendly phosphate surface treatment has been developed, which has the same performance as the traditional one, meanwhile, there is no toxic heavy metal in the phosphating solution and sealing solution. A phosphate coating is fabricated on the surface of X70 pipeline steel. The performance of phosphate coating is studied via the morphology analysis, comprehensive performance, linear polarization and electrochemical impedance spectroscopy methods. The results show that the phosphating film allows the corrosion current density of X70 pipeline steel to drop from 55.105 μA/cm² to35.719 μA/cm². After silicate sealing treatment, the corrosion current density dropped to 0.043μA/cm². The phosphating film is smooth with many pores. After silicate sealing treatment, the film becomes a high dense film which inhibits good corrosion protection of metal.

Key words: phosphate surface teatment, heavy metal, environmental friendly, silicat, sealing

中图分类号: 

• TQ639