In this study,to enhance the coercivity and high-temperature stability of hot-deformed PrNd-Fe-B magnets,the NdHoAlGa alloy was utilized as a diffusion source and a dual-alloy diffusion process was employed to enhance...In this study,to enhance the coercivity and high-temperature stability of hot-deformed PrNd-Fe-B magnets,the NdHoAlGa alloy was utilized as a diffusion source and a dual-alloy diffusion process was employed to enhance the room temperature coercivity from 1.72 to 2.28 T.For the magnet doped with7 wt%Nd_(72.3)Ho_(13).8Al_(2.3)Ga_(11.7),within the temperature range from 20 to 200℃,the remanence temperature coefficient a increases from-0.16%/℃to-0.14%/℃,and the coercivity temperature coefficientβincreases from-0.49%/℃to-0.43%/℃.By controlling grain boundary(GB)phases and optimizing the main phase simultaneously,Ga was induced to motivate the formation of non-ferromagnetic GB phases,reducing the size of grains and intergranular exchange coupling.Additionally,Ho was diffused into the main phase,forming(Pr,Nd,Ho)-Fe-B phase,which enhances the magnetic crystalline anisotropy field of the main phase grains at high temperatures.展开更多
基金Project supported by the National Key Research and Development Program of China(2022YFB3503403)the Inner Mongolia Major Technology Project(2021ZD0035)+1 种基金the Ningbo Natural Science Foundation(2023J343)the Science and Technology Innovation 2025 Major Project of Ningbo(2022Z106)。
文摘In this study,to enhance the coercivity and high-temperature stability of hot-deformed PrNd-Fe-B magnets,the NdHoAlGa alloy was utilized as a diffusion source and a dual-alloy diffusion process was employed to enhance the room temperature coercivity from 1.72 to 2.28 T.For the magnet doped with7 wt%Nd_(72.3)Ho_(13).8Al_(2.3)Ga_(11.7),within the temperature range from 20 to 200℃,the remanence temperature coefficient a increases from-0.16%/℃to-0.14%/℃,and the coercivity temperature coefficientβincreases from-0.49%/℃to-0.43%/℃.By controlling grain boundary(GB)phases and optimizing the main phase simultaneously,Ga was induced to motivate the formation of non-ferromagnetic GB phases,reducing the size of grains and intergranular exchange coupling.Additionally,Ho was diffused into the main phase,forming(Pr,Nd,Ho)-Fe-B phase,which enhances the magnetic crystalline anisotropy field of the main phase grains at high temperatures.