（1. School of Materials Science and Engineering， Shanghai University， Shanghai 200444， China 2. CAS Key Laboratory of Magnetic Materials and Devices， Ningbo Institute of Materials Technology and Engineering， Chinese Academy of Sciences， Ningbo 315201， China）
Abstract：Anisotropic Nd-Fe-B magnets were prepared by hot deformation process. Nano-particles with high melting point， such as WC， BN and ZrO2 were mixed with the Nd-Fe-B melt-spun ribbons before hot pressing process. The effects of different additions on the magnetic properties and microstructures of the hot-deformed magnets were investigated. The results show that the variation in the remanence is not obvious after adding micro additions. Oxide?nano-particles significantly decrease the coercivity of the hot-deformed magnets， while coercivity of the magnets with carbide addition is enhanced. The optimum magnetic properties are obtained at hot-deformed magnet with WC addition. The remanence thermal stability of the magnet is improved， while the coercivity temperature coefficient is hardly affected after adding WC particles. The reversible magnetization of the magnet shows no obvious peak value after adding WC nanoparticles， indicating that the addition of WC nanoparticles inhibits the growth of coarse crystal regions in the hot-deformed magnet and makes the microstructure of the magnet more uniform. At the same time， a new Fe2W phase forms at the WC-aggregated region.
郑晓芬，陈仁杰，雷 芳，李 东，闫阿儒. 高熔点纳米颗粒添加对热变形Nd-Fe-B磁体性能与微观结构的影响[J]. , 2018, 28(06): 42-46.
ZHENG Xiao-fen，，CHEN Ren-jie，LEI Fang，LI Dong，YAN A-ru. Impact of nano-particles with high-melting point on magnetic properties and microstructures of hot-deformed Nd-Fe-B magnet. , 2018, 28(06): 42-46.
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2018, Vol. 28 
