Correlation between microstructure and magnetic properties of Nd-Fe-Cr-B magnets

Author

Leonowicz, M.

Author_Institution

Inst. for Mater. Sci. & Eng., Warsaw Univ. of Technol., Poland

Volume

26

Issue

5

fYear

1990

fDate

9/1/1990 12:00:00 AM

Firstpage

2628

Lastpage

2630

Abstract

Sintered magnets of (Nd₁₆Fe₇₆B₈) _1-xCr_x and (Nd₁₈Fe₇₄B₈)_1-xCr_x have been prepared by blending Cr powders of different particle sizes with the master magnet powder before sintering. Cr addition is shown to produce changes in the coercive field strength depending on the amount and particle sizes of the Cr powder. The coercivity increase is caused by pinning of domain walls at small inclusions in the intermediate phase and by improved isolation of the hard magnetic grains. Deterioration of coercivity results from a decrease in the intrinsic properties of Nd₂(Fe, Cr)₁₄B phase and nucleation of domain walls at large FeCr inclusion

Keywords

boron alloys; chromium alloys; coercive force; crystal microstructure; ferromagnetic properties of substances; iron alloys; magnetic domain walls; neodymium alloys; permanent magnets; (Nd₁₆Fe₇₆B₈)_1-xCr _x; (Nd₁₈Fe₇₄B₈)_1-xCr _x; Nd-Fe-Cr-B; coercive field strength; domain wall pinning; hard magnetic grains; intermediate phase; intrinsic properties; magnetic properties; microstructure; nucleation; particle sizes; sintered magnets; small inclusions; Chromium; Coercive force; Iron; Magnetic domain walls; Magnetic domains; Magnetic properties; Magnets; Microstructure; Neodymium; Powders;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.104820

Filename

104820