添加稀土引致的磷化膜变化与促进机制  

INFLUENCE OF RARE EARTH NITRATE ADDITION ON ZINC PHOSPHATE COATINGS ON STEEL

作　　者：邝钜炽[1] 

机构地区：[1]佛山科学技术学院材料与精细化工研究所,佛山528000

出　　处：《腐蚀科学与防护技术》2006年第3期190-191,共2页Corrosion Science and Protection Technology

摘　　要：用能谱与SEM分析,发现加入稀土硝酸盐(REN)后明显提高了无定形晶体Zn2Fe(PO4)2在磷化膜表面的覆盖率,而使得膜的耐蚀性能提高.此时膜内相关元素含量比例发生了变化:P增大,Zn减小,可见磷对膜耐蚀性的贡献比锌大.讨论认为,稀土硝酸盐是一个有良好载氧能力的催化剂,具有良好的成核促进作用和阴极去极化作用,从而能加速磷化并使膜的耐腐蚀性能提高.Through observation of surface morphology of the zinc phosphate coatings on a steel by SEM, it was ascertained that the coatings gained in a bath with REN addition, incomparison to the coatings got in a bath without REN, show better corrosion resistance because of increasing of covering rate of Zn2Fe（PO4）2 crystals on the surface, as well as of increasing P content, while decreasing Zn content of the coatings. Finally the relevant mechanism was also discussed.

关 键 词：稀土(RE) 稀土硝酸盐(REN) 磷化膜 形貌 机制 

分 类 号：TG178[金属学及工艺—金属表面处理]