铈基钝化法在金属防护中的应用研究进展

Research Progress of Cerium-based Passivation Methods in Metal Protection

铈盐由于其自身无污染、成本低、性能好、用途广等优点,已成为代替铬酸盐钝化的重要方法之一。简要总结了国内外研究人员的发现,得出铈盐可以自行成膜,且铈盐有着良好的自愈能力。同时,也发现纯铈膜的防腐效果不是很理想,易出现裂纹、附着力差等问题。为解决此问题,可以将铈盐与其他金属盐结合,得到混合钝化液,所得到的复合膜效果较好,能减少裂纹的形成;也可以在铈盐钝化液中加入有机化合物,形成的有机和无机复合钝化膜效果更佳,防腐效果甚至高于铬酸盐技术。铈盐以及铈盐复合钝化膜能广泛地应用在各类金属及金属合金表面,极大程度地扩展了铈盐钝化液的应用范围,提高了在工业上的使用率。对铈盐钝化液的机理、钝化方法、应用领域等方面的最新进展进行简单地总结与探讨。为解决铈盐钝化液在钝化机理以及钝化方法方面存在的不足,对最新的工艺方法或配方改善方法进行了提炼,并对未来铈盐钝化液能有效解决原铬基钝化液的污染问题和提高涂层的防腐能力进行了展望。

Cerium-based passivation has become one of the important methods to replace chromate passivation because of the pollution-free,low cost and good performance of cerium salt.The mechanism of cerium salt is based on blocking the cathode area of the material,thereby reducing the cathode reaction rate.This article briefly summarizes the findings of domestic and foreign researchers based on a large number of experiments,and concludes that cerium salt can form a film by itself,which has a good self-healing ability.At the same time,it is also concluded that the effect of pure cerium film is not very good,and problems such as cracks and weak adhesion are prone to appear.To address the problem,the cerium salt can be combined with other metal salts,and the obtained composite film has a better effect and slightly reduces the formation of cracks;it is also possible to add organic compounds to the cerium salt to form an organic and inorganic hybrid passivation solution.The composite passivation film has a better effect,and its anti-corrosion effect is even higher than that of chromate technology.The cerium salt and the cerium-based composite passivation film can be widely used on the surface of various metals and metal alloys,thus the application range of cerium salt passivation solution is expanded greatly,with fast increasing utilization rate in industry.The article briefly summarizes and discusses the recent progress of cerium salt passivation solution,such as the mechanism,passivation method and application fields.In order to overcome the deficiencies of the cerium salt passivation solution in the passivation mechanism and passivation methods,the latest technological methods or formula improvement methods have been refined,and in the future cerium salt passivation solute is highly possible to not only effectively solve the pollution problem caused by chromium-based passivation solution,but also improve the anti-corrosion ability of the coating.