Effect of grain boundary diffusion of terbium on mode of mechanical fracture of sintered NdFeB magnets  

作　　者：Zexin Lu Tinghui Wang Jianjun Jiang Bizhang Zheng Lijing Yang Xingqi He Anli Lin Shengzhi Dong Zhenlun Song 

机构地区：[1]CAS Key Laboratory of Magnetic Materials and Devices,Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology,Ningbo Institute of Materials Technology and Engineering,Chinese Academy of Sciences,Ningbo,315201,China [2]Faculty of Mechanical Engineering and Mechanics,Ningbo University,Ningbo,315211,China [3]Ningbo Xinqi Precision Magnetism Steel Co.,Ltd..,Ningbo,315156,China [4]Center for Advanced Measurement Science,National Institute of Metrology,Beijing,102200,China [5]Division of Functional Materials,Central Iron&Steel Research Institute,Beijing,100081,China

出　　处：《Journal of Rare Earths》2024年第4期696-704,共9页稀土学报（英文版）

基　　金：Project supported by the National Key Research and Development Program of China(2021YFB3502902);the Key Research and Development Program of Ningbo(2021Z024)。

摘　　要：Grain boundary diffusion process(GBDP)is a widely used method of increasing the coercivity of sintered NdFeB magnets.In this study,the effects of the GBDP on the bending strength and microhardness of sintered NdFeB magnets and the fracture mode were investigated.Results show that the bending strength of magnets is reduced by pickling and heat treatment and greatly recove rs after heavy rare earth element(Tb)grain boundary diffusion.The pickling and the heat treatment cause a slight decrease in microhardness.Compared with the recovery of the bending strength,the hardness decreases after the GBDP.The fracture mode of bended magnets changes from intergranular to transgranular.This study helps in further improving the mechanical and magnetic properties of sintered NdFeB magnets.

关 键 词：Sintered NdFeB magnets Grain boundary diffusionprocess Bending strength Heavy rare earth element COERCIVITY 

分 类 号：TF046.4[冶金工程—冶金物理化学]