Influence of the recrystallization processes on the structure and magnetic properties of the Nd2Fe14B/alpha-Fe nanocomposites

• Published in: Journal of Optoelectronics and Advanced Materials Vol. 9; no. 6; pp. 1825 - 1828
• Main Authors: Kappel, W, Codescu, M M, Valeanu, M, Stancu, N, Pintea, J, Lifei, F, Jianu, A, Patrol, D, Patroi, E
• Format: Journal Article
• Language: English
• Published: 01.06.2007
• ISSN: 1454-4164

Exchange-coupled Nd2Fe14B/alpha-Fe nanocomposite magnets receives considerable research interest, because these are regarded as promising candidate materials for permanent magnets, with an adequate performance while keeping the content of relatively expensive Nd low. The advantage of these new magnetic materials are the lower rare earth content (and consequently, cheaper magnets with better corrosion resistance). The Nd2Fei4B/alpha-Fe nanocomposites were obtained by recrystallisation treatment from an amorphous phase prepared by melt-spinning. For Fe contents, between 83 and 85 at. %, we have obtained the hardening of the a-Fe phase by exchange interactions between the hard Nd2Fe14B phase and the soft a-Fe phase. The evolution of the structure and main magnetic characteristics after different annealing conditions was studied. For all isotropic permanent magnets obtained from the prepared nanocomposites was measured a remanence ratio higher than 0.5, which confirm the existence of the mentioned exchange interactions.