Research of Microstructure and Anticorrosion Property of Zn-Cr Coating on Sintered NdFeB Permanent Magnet

来源期刊：Journal of Rare Earths2006年第S2期

论文作者：陈玲 韩婧 于升学

文章页码：203 - 206

摘    要：Zn-Cr coating was obtained on the surface of sintered NdFeB permanent magnet by immersing special solution and baked at 290～310 ℃ for 30 min. The anticorrosive property of the coating was studied by 3.5% salt solutions immersion test. The results show the value of of Zn-Cr coating is less than that of bare NdFeB substrate, and the Zn-Cr coating makes sacrifice to protective NdFeB substrate as anode in corrosion medium. The microstructure analysis of the Zn-Cr coating was performed by means of optical microscopy and scanning electron microscopy. The results indicate that Zn-Cr coating was covered even on the surface of the substrate and Zn flakes piles nearly parallel to matrix, which discouraged corrosive medium from solution to the substrate. The compositions of coating were studied by means of XRD, XPS and EDS, which consists of Zn（0）, Zn（Ⅱ）, Cr（Ⅲ） and a little of Cr（Ⅵ）, and the Cr（Ⅵ） processes passivation function to Zn flake and NdFeB substrate. Therefore the NdFeB after Zn-Cr coating treatment processes high anticorrosion property. And the coating has a little of negative effects on magnetic properties.