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

fYear

2015

fDate

11-15 May 2015

Firstpage

1

Lastpage

1

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;

fLanguage

English

Publisher

ieee

Conference_Titel

Magnetics Conference (INTERMAG), 2015 IEEE

Conference_Location

Beijing

Print_ISBN

978-1-4799-7321-7

Type

conf

DOI

10.1109/INTMAG.2015.7156590

Filename

7156590