Fabrication and characterization of 1-dimensional neodymium-iron-boron fibers using new reduction-diffusion process

Abstract

A novel method for the synthesis of neodymium-iron-boron (Nd-Fe-B) fibers is demonstrated in this study by adopting three continuous processes: electrospinning, step heat treatment, and a new process comprising facile reduction-diffusion. The structural and crystalline studies revealed that as-spun precursor fibers were transformed into FeNdO3, Fe2O3, and NdBO3 phases by non-isothermal heat treatment; further, the oxide mixture fibers were reduced to a single Nd2Fe14 B phase by the facile reduction-diffusion process. A facile reduction-diffusion process in this paper can obtain Nd2Fe14 B fibers without brokenness; this is because it leads to the formation of a thin salt layer on Nd2Fe14 B fiber surface when reacting to by-product CaO granules. The BH(max)of Nd2Fe14 B fibers was exhibited by 3.34 MGOe. To our knowledge, this is the first attempt to fabricate 1-D Nd2Fe14 B fibers successfully using a new reduction-diffusion process. This work provides a simple way to prepare 1-D hard magnetic Nd-Fe-B fibers with excellent shape anisotropy attributed to a high aspect ratio. (C) 2020 Published by Elsevier B.V.