Effect of coarse grains on magnetic properties of Nd-Fe-Co-B-Ga die-upset magnets

Author

Nozawa, Yasuto ; Tanigawa, Shigeho ; Tokunaga, Nasaaki

Author_Institution

Hitachi Metals Ltd., Saitama, Japan

Volume

26

Issue

5

fYear

1990

fDate

9/1/1990 12:00:00 AM

Firstpage

1724

Lastpage

1726

Abstract

Coarse grains contained in Nd-FeCo-Ga-B hot-pressed and die-upset magnets are examined. Coarse grains contained in hot-pressed magnets are found to maintain their shapes during die upsetting and to increase deformation resistance B_r, H_k, and (BH)_max of die-upset magnets decrease with increase in the volume fraction of coarse grains. Equiaxed coarse grains nucleate and grow during melt spinning. Columnar coarse grains grow during hot pressing. It is shown that the volume fraction of coarse grains before die upsetting should be minimized to increase (BH)_max

Keywords

boron alloys; cobalt alloys; ferromagnetic properties of substances; gallium alloys; hot pressing; iron alloys; magnetic properties of fine particles; melt spinning; neodymium alloys; Nd-Fe-Co-B-Ga; coarse grains; deformation resistance; die-upset magnets; hot-pressed magnets; magnetic properties; melt spinning; volume fraction; Amorphous magnetic materials; Amorphous materials; Grain size; Magnetic flux; Magnetic materials; Magnetic properties; Magnets; Neodymium; Scanning electron microscopy; Surface cracks;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.104505

Filename

104505