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Home > Issues > Volume 1 (1996) > No.2(pp.55-100)
Study on the HDDR Characteristics of Nd16Fe76-xB8Zrx (x=0-2.0) Alloys and the Magnetic Properties of the HDDR Materials
Journal of Magnetics, Volume 1, Number 2, 31 Dec 1996, Pages 75-81
H.W. Kwon(Department of Materials Science and Engineering, Pukyoung National University)

 Alloys with compositions based on Study on Nd16Fe76-xB8Zrx (where x=0-2.0) have been studied to see the effect of Zr addition on HDDR characteristics. A particular emphasis was place upon the anisotropy of the HDDR material. Anisotropy of the HDDR powder material has been evaluated by comparing the remanence values of the aligned sample measured along the aligning direction and the direction perpendicular to it. The HDDR characteristics of the alloys were investigated by means of DAT and TPA. Magnetic chracterisation of the HDDR processed materials was performed using a VSM and a TMA. The magnetic domain structure of the HDDR materials was examined by means of polarised microscope using a solid HDDR processed material. It has veen found that small addition (0.1 at %) of Zr to Nd-Fe-B-type alloy retards thedisproportionatio kinetics of the hydrogenated material. Desorption characteristic of the disproportionated materials has been found not to be affected significantly by the Zr addition. The Zr addition has been found to facilitate size of the powder. As the particle size decreases, the intrinsic coercivity decreases radically, and this is explained in terms of structural damage and/or oxidation caused during mechanical milling. It has also been found that the degree of alignment representing the anisotropic character of the HDDR powder is enhanced with decreasing particle size.

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