Effect of Ball Milling and Crystallizing on Magnetic Properties of Nanocomposite Nd_2Fe_(14)B/α-Fe Permanent Magnetic Material

摘要

Nanocomposite Nd_2Fe_(14)B/α-Fe magnetic material had been prepared by ball milling Nd8Fe86B6 as-cast alloy in Argon and subsequent crystallizing. Influence of ball milling on their magnetic properties had been investigated by means of X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Vibrating Sample Magnetometer (VSM) etc. The results show that Nd_2Fe_(14)B grain are refined quickly and grain size of α-Fe decreases while extending milling time. After milling for 25h, grain size of α-Fe reaches about 7nm. Magnetic properties increase with milling time. Milled for 25h and crystallizing at 700°C for 30 minutes, samples have the best comprehensive magnetic properties (remanence, coercivity and magnetic energy product). To obtain nanocomposite permanent materials with high magnetic properties, it is necessary to combine ball milling with crystallizing.