Nd2Fe14B magnetic nanoparticles have been successfully produced using a surfactant-assisted ball milling technique. The nanoparticles with different size about 6, 20 and 300 nm were obtained by a size-selection process. Spin-reorientation transition temperature of the NdFeB nanoparticles was then determined by measuring the temperature dependence of DC and AC magnetic susceptibility. It was found that the spin-reorientation transition temperature (Tsr) of the nanoparticles is strongly size dependent, i.e., Tsr of the 300 nm particles is lower than that of raw materials and a significant decrease was observed in the 20 nm particles.
@article{arxiv.1005.1706,
title = {Size-dependent spin-reorientation transition in Nd2Fe14B nanoparticles},
author = {Chuanbing Rong and Narayan Poudyal and J. Ping Liu},
journal= {arXiv preprint arXiv:1005.1706},
year = {2015}
}