Growth Kinetics of Nd<sub>2</sub>Fe<sub>14</sub>B Phase during Hydrogen-Induced Reverse Phase Transformation in Nd<sub>2</sub>Fe<sub>14</sub>B Type Nanocrystalline Magnetic Alloy
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Abstract
The influence of hydrogen pressure on kinetics of growth of Nd<sub>2</sub>Fe<sub>14</sub>B phase during hydrogen-induced reverse phase transformations in the industrial Nd<sub>2</sub>Fe<sub>14</sub>B 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 Nd<sub>2</sub>Fe<sub>14</sub>B 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.
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