Reduction diffusion process for preparation of Nd-Fe-B based alloy

Starting from the ultra fine Nd-Fe-B nanoparticle synthesized by chemical reduction, Nd-Fe-B based alloy was successfully prepared by reduction-diffusion process. The amorphous Nd-Fe-B based nanoparticle was synthesized from reduction of FeCl
₂
and NdCl
₃
with NaBH
₄
as a reducing agent in aqueous solution. Precipitates composed of Fe-B based, Fe
₂
O
₃
, and Nd
₂
O
₃
was used as starting materials. After the synthesized Fe
₂
O
₃
phase was changed to alpha-Fe phase with high-purity mixed gas, Nd
₂
O
₃
phase was reduced by calcium hydride. The obtained Nd-Fe-B based materials are fine crystalline powder, and the particle size of these materials can be controlled to about a few-micro. The magnetic properties of the Nd-Fe-B based alloy were characterized by vibrating sample magnetometer (VSM) and X-ray powder diffraction (XRD). The size of nanoparticles was investigated by transmission electron microscopy (TEM), scanning electron microscopy (SEM) and field emission scanning electron microscopy (FE-SEM). Chemical compositions were examined using energy dispersive X-ray spectroscopy (EDX).