Effect of hydrogen pressure on growth kinetics of Nd2Fe14B phase during hydrogen-induced reverse phase transformation in Nd2Fe14B type hard magnetic alloy

Received: 16 May 2011; Revised: 16 June 2011; Accepted: 21 June 2011
Citation: S.B. Rybalka. Effect of hydrogen pressure on growth kinetics of Nd2Fe14B phase during hydrogen-induced reverse phase transformation in Nd2Fe14B type hard magnetic alloy. Lett. Mater., 2011, 1(2) 96-101
BibTex   https://doi.org/10.22226/2410-3535-2011-2-96-101

Abstract

 The effect of initial hydrogen pressure on growth kinetics of Nd2Fe14B phase during hydrogen-induced reverse phase transformation 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 growth of Nd2Fe14B phase 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-Hillert-Smirnov kinetic models the kinetic equation for describing of influence of initial hydrogen pressure on the isothermal kinetic diagram for this transformation has been proposed.

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