Title :
Microstructural control of Nb addition in nanocrystalline hard magnets with different Nd content
Author :
Wu, Y.Q. ; Kramer, M.J. ; Chen, Z. ; Ma, B.M. ; Ping, D.H. ; Hono, K.
Author_Institution :
Ames Lab., Iowa State Univ., Ames, IA, USA
Abstract :
The effects of Nb addition on the hard magnetic properties and microstructure evolution in Nd8Fe78-xCo8B6Nbx and Nd12Fe82-xB6Nbx nanocrystalline alloys are presented. Low Nd containing alloys consist of α-Fe and Nd2Fe14B phases. The Nd12Fe80.5B6Nb1.5 alloy probably contains NbFeB phase besides the α-Fe and Nd2Fe14B phases. It is found that Nb atoms tend to enrich at grain boundary regions, resulting in refined microstructure and significantly improved coercivity over a range of conventional Nd-Fe-B alloys.
Keywords :
alloying additions; boron alloys; cobalt alloys; coercive force; crystal microstructure; ferromagnetic materials; grain boundaries; iron alloys; magnetic hysteresis; nanostructured materials; neodymium alloys; niobium alloys; permanent magnets; remanence; transmission electron microscopy; α-Fe phase; HREM; Nb addition; Nd12Fe82-xB6Nbx; Nd12Fe82-xB6Nbx nanocrystalline alloys; Nd2Fe14B phase; Nd8Fe78-xCo8B6Nbx; Nd8Fe78-xCo8B6Nbx nanocrystalline alloys; TEM; X-ray analyses; coercivity; energy product; grain boundary region; hard magnetic properties; hysteresis loops; microstructure evolution; permanent magnets; refined microstructure; remanence; Cobalt alloys; Coercive force; Iron alloys; Magnetic properties; Magnets; Microstructure; Neodymium; Niobium alloys; Remanence; Soft magnetic materials;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2003.815751
