Title :
Coercivity enhancement of Dy-free sintered Nd-Fe-B magnets by grain refinement and induction heat treatment
Author :
Chen, L. ; Cao, X. ; Guo, S. ; Ding, G. ; Di, J. ; Yan, C. ; Yan, A.
Author_Institution :
Zhejiang Province Key Lab. of Magn. Mater. & Applic. Technol., Ningbo Inst. of Mater. Technol. & Eng., Ningbo, China
Abstract :
Sintered Nd-Fe-B magnets have been widely applied in traction motors and wind power generators. To meet enough high coercivity for these applications, heavy rare earth elements (Dy/Tb) was substituted for Nd since the magnetocrystalline anisotropy field of Dy2Fe14B phase is much higher than that of Nd2Fe14B. However, due to the limited resources and high cost, a new way that can enhance the coercivity without using Dy is strongly desired. Here we report an enhancement of coercivity in Dy-free sintered Nd-Fe-B magnets through modifying the microstructure of grain boundaries by grain refinement and high-frequency induction heat treatment (HIHT).
Keywords :
boron alloys; coercive force; grain boundaries; grain refinement; heat treatment; iron alloys; neodymium alloys; Dy-free sintered Nd-Fe-B magnets; NdFeB; coercivity enhancement; grain boundary microstructure; grain refinement; heavy rare earth elements; high-frequency induction heat treatment; magnetocrystalline anisotropy field; traction motors; wind power generators; Annealing; Coercive force; Electromagnetic heating; Grain boundaries; Magnetic resonance imaging; Perpendicular magnetic anisotropy;
Conference_Titel :
Magnetics Conference (INTERMAG), 2015 IEEE
Conference_Location :
Beijing
Print_ISBN :
978-1-4799-7321-7
DOI :
10.1109/INTMAG.2015.7156590
