Preparation and properties of hot-deformed magnets processed from nanocrystalline/amorphous Nd-Fe-B powders  

作　　者：Peng Zhao Yang Luo Dun-Bo Yu Hai-Jun Peng Wen-Long Yan Zi-Long Wang Xin-Yuan Bai 

机构地区：[1]National Engineering Research Center for Rare Earth Materials,General Research Institute for Nonferrous Metals,Beijing,100088,China [2]Grirem Advanced Materials Co.,Ltd,Beijing,100088,China

出　　处：《Rare Metals》2021年第8期2033-2039,共7页稀有金属（英文版）

基　　金：financially supported by the National Key Research and Development Program(No.2016YFB0700902)。

摘　　要：The hot-deformed magnets processed from nanocrystalline/amorphous Nd-Fe-B powders were preparedunderdifferenthot-pressingtemperatures(600-750℃,at intervals of 25℃)by the self-made hotpressing equipment.The microstructure and magnetic properties of hot-deformed magnets prepared at different temperatures were also investigated.When the temperature is above 650℃,the density of magnet reaches 7.5 g·cm^(-3).The optimum magnetic properties of magnetic induction intensity of B_(r)=1.3 T,optimum energy product of(BH)_(max)=282.5 kJ·m^(-3),intrinsiccoercivityof H_(cj)=1130.0 kA·m-1 of hot-deformed magnets are obtained at hot-pressing temperature of 650℃.X-ray diffractometer pattern shows that the(00 L)texture has been obtained.For the microstructural characteristic,on the one hand,the good magnetic performance is attributed to the fine platelet-like grains with an average length of 410-440 nm at the hot-pressing temperature range from625 to 675℃.On the other hand,the unaligned coarse grains are observed in all the samples.And the areal fraction of those is gradually increasing with the rise of the hot-pressing temperature,which tends to deteriorate the magnetic properties.The composition map shows the accumulation of Nd/Pr-rich phase in the coarse grains’region.

关 键 词：Nanocrystalline/amorphous powders Hotpressing temperature Hot-deformed Magnets Magnetic properties Microstructure 

分 类 号：TB383.3[一般工业技术—材料科学与工程]