Properties of rapidly solidified Nd-Fe-Ga-Co-B alloys

Author

Panchanathan, V. ; Croat, J.J.

Author_Institution

Gen. Motors Corp., Anderson, IN, USA

Volume

25

Issue

5

fYear

1989

fDate

9/1/1989 12:00:00 AM

Firstpage

4111

Lastpage

4113

Abstract

Investigations carried out to study the properties of rapidly solidified Nd-Fe-B alloys containing gallium and cobalt are reported. The gallium content that gives maximum room-temperature B_r and BH_max was found to be 0.6 wt.%. Further investigations were carried out with 0.6 wt.% gallium and varying cobalt contents. Transmission electron micrographs of the ribbons indicate a three-phase structure as compared to the two-phase structure in Nd-Fe-B alloys. The three phases are Nd₂(Fe,Co)₁₄B, Nd(Fe,Co)₄B, and a neodymium-iron-gallium grain boundary phase. The latter phase is depleted in iron, which is believed to increase the coercive force by increasing its effectiveness as a pinning site. Anisotropic magnets were prepared from the above alloys by hot deformation techniques. Energy products up to 40 MGOe were achieved with a magnet uniformity of ±1.5 MGOe through the cross section

Keywords

boron alloys; cobalt alloys; coercive force; ferromagnetic properties of substances; gallium alloys; iron alloys; neodymium alloys; permanent magnets; rapid solidification; remanence; transmission electron microscope examination of materials; TEM; anisotropic magnets; coercive force; energy product; grain boundary phase; hot deformation; magnet uniformity; permanent magnets; pinning site; rapidly solidified Nd-Fe-Ga-Co-B alloys; remanence; three-phase structure; Anisotropic magnetoresistance; Annealing; Cobalt; Coercive force; Gallium alloys; Human computer interaction; Magnetic materials; Magnetic properties; Magnets; Temperature;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.42538

Filename

42538