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

S.B. Rybalka1
1Donetsk National Technical University, 58 Artem St., 83000 Donetsk
Abstract
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. 
Received: 07 December 2011   Accepted: 16 February 2012
Views: 68   Downloads: 7
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