用于钕铁硼永磁材料镀锌的钝化工艺研究

Study on Passivation Process for Zinc Plating of Nd-Fe-B Permanent Magnet

电镀锌是钕铁硼永磁材料产品零件表面处理最常用的方法之一,而钝化是影响产品质量的关键,直接关系防腐性能的优劣。为增加镀锌钝化膜的致密性,提高产品耐腐蚀性能,采用高铬钝化和低铬钝化相结合的二次钝化工艺进行表面处理,随同高铬一次钝化工艺做对比。可靠性测试表明:该工艺明显提高了镀锌层的耐腐蚀能力,中性盐雾试验水平可达200 h以上;同时提高了钝化膜层的致密性。

Electrogalvanizing is one of the most commonly used surface treatment methods of NdFeB permanent magnet parts,and passivation is the key to affect the quality of products, directly related to the merits of anti-corrosion performance. In order to increase the compactness of the galvanized passivation film and improve the corrosion resistance of the product, the secondary passivation process combining high chromium passivation and low chromium passivation was used for surface treatment, and the comparison was made with the high chromium primary passivation process. The reliability test shows that the corrosion resistance of the zinc coating is improved obviously by this process, and the neutral salt spray test level can reach more than 200 hours. At the same time, the compactness of the passivation film is improved.