烧结方式对NdFeB磁体磁性能的影响

Effect of Sintering Processing on Magnetic Performance of Sintered NdFeB Magnet

在烧结坯放气完毕后即采用不同的烧结方式处理NdFeB磁体。研究发现,真空烧结样品比气氛烧结样品的抗氧化和抗腐蚀能力强;但是,样品的Br、Hcj和(BH)max则要低一些。SEM分析表明,气氛烧结样品与真空烧结样品相比,晶粒更致密、均匀,缺陷也较少。试验结果指出,气氛烧结是一种较好的烧结方式,可以降低生产成本和稳定磁性能。

NdFeB magnet was teated by the different sintering processing after samples＇ ending processing of gas release, It was found that after vacuum sintering processing, the sample＇s surface was clean, silver, and it was not easy to be oxidized and corroded, But after sintering processing in argon, the sample＇s surface was gray black and the sample was easy to be oxidized or corroded, On the other hand, the latter magnetic performance was better, more homogeneous and stable than the former. The SEM results show that the former had more and bigger pores, more linear grain boundary defects after Nd-rich phase＇s volatilization than the latter, The research results show that sintering processing in argon is good and may decrease productive cost and steady magnetic performance.