钢铁材料电镀镉的研究现状

Recent Developments in Cadmium Electroplating of Iron and Steel Materials

钢铁材料广泛地应用于诸多工业领域中,但其表面耐蚀性差,发生于材料表面的腐蚀会导致材料失效。镉与空气接触时会迅速氧化并形成致密的保护性氧化膜,因此表面镀镉可以有效地提高钢铁材料表面的耐蚀性。从电镀镉技术的具体应用出发,综述了用于钢铁表面防护的电镀镉技术和用于表面修复的电刷镀镉技术的应用现状。镀镉层作为阳极保护层,实现了对钢铁材料的防护。在镀液中添加钛盐后,形成的镉钛镀层比单纯的镀镉层具有更优异的耐蚀性和更好的低氢脆性。电刷镀镉作为一种特种镀镉技术,可用作镀镉局部破损件的补镀和修复。针对电镀镉废水对环境和人体的高危害,简要阐述了化学法、物理化学法、生物法三种电镀镉废水的处理方法,且微生物法具有良好的发展前景。最后,展望了钢铁材料电镀镉技术的相关研究思路和方法。

Iron and steel materials have been extensively used in various industrial fields. However, iron and steel materials are prone to fail due to their poor surface corrosion resistance. Cadmium （Cd） can readily form a dense protective oxide film when being exposed to air. Therefore, cadmium electroplating has become one of the effective ways to improve the corrosion resistance of iron and steel materials. This review began with the specific applications of cadmium electroplating technology. The application status of cadmium electroplating techniques was introduced. One was conventional Cd electroplating technique for protecting iron and steel surface, and the other was brush Cd electroplating for repairing surface. Cd electroplating coating acting as an anodic protective coating can realize surface protection of iron and steel. When titanium （Ti） salts were added into the cadmium electrolyte, the formed Cd-Ti electroplating coating showed better corrosion resistance and lower hydrogen embrittlement than that of pure Cd electroplating coating. As a kind of special electroplating technology, brush Cd electroplating can be widely used in repairing electroplating and surface repairing of local damaged parts subject to Cd electroplating. In view of the high harmfulness of wastewater produced by Cd electroplating to environment and human beings, chemical method, physical-chemical method and biological method for treating the wastewater were summarized. Among the mentioned ways, microbiological method indicated a promising development prospect. Finally, research ideas and methods regarding Cd electroplating technique of iron and steel materials were previewed.