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http://dx.doi.org/10.4150/KPMI.2010.17.1.023

Improvement of Microstructural Anisotropy of Nd-Fe-B-Ga-Nb Alloy by the Control of Hydrogen Reaction  

Lee, S.H. (Korea Institute of Materials Science)
Kim, D.H. (Korea Institute of Materials Science)
Yu, J.H. (Korea Institute of Materials Science)
Lee, D.W. (Korea Institute of Materials Science)
Kim, B.K. (Korea Institute of Materials Science)
Publication Information
Journal of Powder Materials / v.17, no.1, 2010 , pp. 23-28 More about this Journal
Abstract
HDDR treated anisotropic Nd-Fe-B powders have been widely used for the sheet motors and the sunroof motors of hybrid or electric vehicles, due to their excellent magnetic properties. Microstructural alignment of HDDR treated powders are mostly depending on the hydrogen reaction in disproportionation step, so the specific method to control hydrogenation reaction is required for improving magnetic properties. In disproportionation step, hydrogenation pressure and reaction time were controlled in the range of 0.15~1.0 atm for 15~180 min in order to control the micorstructural alignment of $Nd_2Fe_{14}B$ phase and, at the same time, to improve remanence of HDDR treated magnet powders. In this study, we could obtain a well aligned anisotropic Nd-Fe-B-Ga-Nb alloy powder having high remanence of 12 kG by reducing hydrogen pressure down to 0.3 atm in disproportionation step.
Keywords
HDDR; Disproportionation; Magnetic anisotropy; Remanence; Corecivity;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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