Cu85Sn15晶界添加对NdFeB磁性及抗蚀性的影响

Effect of Intergranular Addition of Cu85Sn15 on Magnetic and Anti-corrosive Properties of NdFeB Magnets

摘要:

本文研究了晶界添加Cu85Sn15对(Pr,Nd)12.6Dy0.9FebalB5.9磁性和抗腐蚀性的影响。结果表明：Cu85Sn15添加量为0.16wt.%时，磁体的磁性和抗腐蚀性最强。NdFeB磁性的增加主要源于材料致密化及晶界相分布均匀化，优化的组织结构也有利于材料抗腐蚀性的提高，此外，掺Cu85Sn15磁体中(Pr,Nd)6Fe13Cu晶界相的出现和富(Pr, Nd)相的减少，减少了晶界区域活化反应通道的形成，增大了电化学腐蚀过程中电荷迁移阻力，降低了腐蚀电流密度，增加了材料的腐蚀抗力。

Abstract:

Effects of Cu85Sn15 intergranular additions on the magnetic and anti-corrosion properties of (Pr,Nd)12.6Dy0.9FebalB5.9 were investigated. Results showed that when 0.16 wt% Cu85Sn15 was added, the NdFeB magnet possessed the maixum values of the magnetic properties and anti-corrosion resistance. The improvement of corrosion resistance mainly arose from the increase in the density and from the optimized distribution of intergranular phases. Also the aforementioned optimization of structure factors benefited the anti-corrosion performance of NdFeB. Additionally, in the Cu85Sn15 doped magnet the occurrence of (Pr,Nd)6Fe13Cu and the decrease in the amount of (Pr, Nd)-rich phase reduced the formation of active reaction channels in the anodic intergranular regions, thus increasing the charge transfer resistance. As a result, the corrosion current density decreased and the corrosion resistance was enhanced.