Effects of Nb addition and/or casting method on the amount of precipitated Fe in NdFeB alloys

Author

liu, W.L. ; Liang, Y.L. ; Ma, B.M. ; Bounds, C.O.

Author_Institution

Rhone-Poulenc Basic Chemicals, Cranbury, NJ, USA

Volume

28

Issue

5

fYear

1992

fDate

9/1/1992 12:00:00 AM

Firstpage

2154

Lastpage

2156

Abstract

A novel method has been developed to measure the amount of precipitated Fe in a series of (Nd_0.9Dy_0.1)_xFe_93.5-x-yNb_yB_6.5 alloys, where x=13, 14, 15, or 17, and y=0 or 0.5. It has been found that the amount of precipitated Fe decreases significantly with increasing rare earth content. Nb has been found to suppress the amount of precipitated Fe by approximately 50% for all compositions studied. Rapid solidification via an inert gas atomization process has been used to further suppress the amount of precipitated Fe in (Nd_0.9Dy _0.1)_xFe_93-xNb_0.5B_6.5 where x=13 and 14. The amount of precipitated Fe can be efficiently decreased, overcoming the problems suggested by the equilibrium phase diagram for these alloys. It is concluded that inert gas atomization offers a promising means to produce alloy powders with fewer Fe-precipitates, and thus sintered magnets with superior magnetic properties and corrosion resistance

Keywords

boron alloys; directional solidification; dysprosium alloys; ferromagnetic properties of substances; iron alloys; magnetisation; neodymium alloys; niobium alloys; permanent magnets; phase diagrams; precipitation; rapid solidification; (Nd_0.9Dy_0.1)_xFe_93.5-x-yNb_yB_6.5; NdFeB alloys; casting method; corrosion resistance; equilibrium phase diagram; inert gas atomization; magnetic properties; precipitated Fe; rapid solidification; sintered magnets; Casting; Chemicals; Composite materials; Corrosion; Iron alloys; Magnetic properties; Microstructure; Niobium alloys; Optical microscopy; Permanent magnets;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.179427

Filename

179427