Growth Kinetics of Nd₂Fe₁₄B Phase during Hydrogen-Induced Reverse Phase Transformation in Nd₂Fe₁₄B Type Nanocrystalline Magnetic Alloy

Sergey Borisovich Rybalka

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DOI: 10.4236/msa.2011.28149                

Abstract

The influence of hydrogen pressure on kinetics of growth of Nd₂Fe₁₄B phase during hydrogen-induced reverse phase transformations in the industrial Nd₂Fe₁₄B hard magnetic alloy has been studied. It has been determined that, as the temperature and the initial hydrogen pressure increase, a reverse phase transformation significantly accelerates. It has been shown that the kinetics of the reverse phase transformation is controlled by the Fe atoms diffusion and that the rate growth of new Nd₂Fe₁₄B phase increase with increase of initial hydrogen pressure. On the base of the Kolmogorov kinetic theory the kinetic equation describing influence of initial hydrogen pressure on the isothermal kinetic diagram for this transformation has been obtained.

Keywords

Intermetallics, Growth Kinetics, Permanent Magnets, Gas–solid Reactions PACS numbers: 64.70.Kd, 68.35.Fx, 66.30.-h

Conflicts of Interest

The authors declare no conflicts of interest.

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