回火工艺对热扩渗PrZn合金烧结态磁体组织和磁性能的影响  

Effect of tempering on magnetic properties and microstructure of Pr Zn-coated NdFeB magnet

作　　者：郭诚君 陈金水[1] 李家节[1,2] 周头军 乐顺聪 刘武杰[1] 

机构地区：[1]江西理工大学材料科学与工程学院,江西赣州341000 [2]江西理工大学工程研究院,江西赣州341000 [3]江西省江铜一台意特种电工材料有限公司,江西南昌330000

出　　处：《金属热处理》2017年第5期108-111,共4页Heat Treatment of Metals

基　　金：国家自然科学基金(51561009);江西省高校科技落地计划项目(KJLD14043);江西省青年科学基金计划项目(20151BAB216005);江西省教育厅研究项目(GJJ14448)

摘　　要：采用磁控溅射技术,在N35烧结态磁体表面沉积一层低熔点PrZn合金,经750℃热扩渗3 h,再在0~500℃进行回火处理。研究了回火工艺对沉积薄膜磁体磁性能及微观组织结构的影响,并对最佳回火工艺处理后烧结磁体热稳定性进行了研究。结果表明,最佳回火温度为500℃,该工艺下,磁体矫顽力由963.96 kA/m提高到1317.14 kA/m,即在原来的基础上增加了36.64%,富Nd晶界相变得连续和光滑,降低了硬磁相之间的磁耦合,改善了晶界相及其附近在反磁化过程中反磁化畴核的形成能力,是矫顽力大幅度提高的主要原因。另外,相对未进行晶界扩散处理的磁体而言,经最佳回火工艺晶界扩散处理后的磁体,在不同温度保温后磁通不可逆损失明显降低,具有更佳的热稳定性。PrZn alloy film was deposited on surface of as-sintered NdFeB magnet by the method of magnetron sputtering, and the samples were treated by thermal diffusing permeation at 750 ℃ for 3 h, and then tempered at 0-500℃. Effects of tempering on magnetic properties and microstructure of the PrZn-coated magnets were studied. Temperature stability of PrZn-coated magnet with the optimum tempering process was also studied. The results show that the optimum tempering temperature is 500℃, the coercivityis increased from 963.96 kA/m to 1317. 14 kA/m with an increase of 36.64% after grain boundary diffusion treatment. Nd-rich phase turns continuous and smooth, reduces the magnetic coupling between the hard magnetic phase and improves the forming ability of the domain of nuclear magnetization in the process of the reversal magnetization of the grain boundary phase and neighboring phase, which is the main reasons to cause the coercivity to upgrade dramatically. In addition, the grain boundary diffusion magnet obtains better thermal stability compared with the original sample, through the optimum tempering process treatment, the magnetic flux irreversible loss obviously decreases in different temperature.

关 键 词：磁控溅射 回火 PrZn合金 烧结钕铁硼 

分 类 号：TM271.3[一般工业技术—材料科学与工程]