钢铁材料电镀镉的研究现状

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。

Recent Developments in Cadmium Electroplating of Iron and Steel Mate-rials

Iron and steel materials have been extensively used in various industrial fields. However, iron and steel are prone to deactivation due to their poor corrosion resistance. Cadmium (Cd) can readily form a dense protective oxide film when it was exposed to air. Therefore, cadmium electroplating has become one of the effective ways to improve the corrosion resistance of the iron and steel materials This review began with the applications of surface cadmium electroplating technology. The status of two different specific examples of cadmium electroplating were introduced. One is the conventional Cd electroplating for surface protection, and the other is brush Cd electroplating for surface repairing. Cd electroplating coating which acts as an anodic protection coating can realize the surface protection of iron and steel. When titanium (Ti) salts were added into the cadmium electrolyte, the formed Cd-Ti electroplating coating could present better corrosion resistance and low hydrogen embrittlement than those of pure Cd electroplating coating. As a kind of special electroplating technology, brush Cd electroplating has been widely used in surface repairing of located damage workpieces. In view of the high harmfulness of Cd electroplating wastewater to environment and human beings, three methods of chemical method, physical-chemical method, and biological method for preventing and controlling the wastewater have been proposed. Among the mentioned ways, microbiological method has indicated a promising development prospect. Finally, the prospect of Cd electroplating related research ideas and methods on iron and steel materials were put forward.