Title :
Effect of Rare-Earth Content on Coercivity and Temperature Stability of Sintered Nd-Fe-B Magnets Prepared by Dual-Alloy Method
Author :
Wenbiao Fu ; Shuai Guo ; Chaowei Lin ; Renjie Chen ; Xincai Liu ; Don Lee ; Aru Yan
Author_Institution :
Key Lab. of Magn. Mater. & Devices, Ningbo Inst. of Mater. Technol. & Eng., Ningbo, China
Abstract :
The influence of rare earth content on coercivity and temperature stability with dual-alloy method has been investigated. It is found that the coercivity of magnets increases rapidly firstly and then slightly with the increasing of rare earth content from the range of 29.5 wt% to 33.5 wt%. The coercivity and the temperature coefficient of coercivity will get better with rare earth content of 31.5 wt%. The result of magnetic anisotropy field of magnet revealed that it almost has no change with different rare-earth content. Scanning electron microscopy (SEM) and Transmission electron microscope (TEM) revealed that continuous thin layers of Nd-rich phase about 4 nm were found along the grain boundaries in the annealed sample at 31.5 wt% rare earth content, while the grain boundary width of magnet exceeds 8 nm at 33.5 wt%.
Keywords :
annealing; boron alloys; coercive force; grain boundaries; iron alloys; iron compounds; magnetic anisotropy; neodymium alloys; permanent magnets; scanning electron microscopy; sintering; transmission electron microscopy; NdFeB; annealing; coercivity; dual alloy method; grain boundary width; magnetic anisotropy field; rare earth content; scanning electron microscopy; sintering; temperature stability; transmission electron microscopy; Annealing; Coercive force; Grain boundaries; Magnetic resonance imaging; Perpendicular magnetic anisotropy; Thermal stability; Coercivity; dual-alloy; rare-earth content; sintered Nd-Fe-B magnet; temperature stability;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2013.2252156