Nanocrystalline microstructure formation during hydrogen-induced phase transformations in Nd2Fe14B hard magnetic alloy

Received  07 December 2011; Accepted  16 February 2012
This paper is written in Russian
Citation: S.B. Rybalka. Nanocrystalline microstructure formation during hydrogen-induced phase transformations in Nd2Fe14B hard magnetic alloy. Lett. Mater., 2012, 2(1) 49-53


The kinetics and features of nanocrystalline microstructure formation during direct and reverse hydrogen-induced phase transformations in Nd2Fe14B alloy has been studied. It has been established that a hydrogen-vacuum treatment carried out in accordance with the kinetic data of transformations in Nd2Fe14 alloy leads to a formation of nanocrystalline homogeneous microstructure with average grains size ~0.3 micrometer. It is shown that carrying out direct and reverse transformations taking into account of kinetic features of transformations as temperature and transformation time allow to avoid abnormal growth processes a main hard magnetic Nd2Fe14B phase that is one of the main factors for permanent magnets obtaining with high coercivity without very complicated and expensive of alloying procedures. 

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