Preparation and Characterization of Nd_2Fe_(14)B/alpha-Fe Nanocomposite Magnetic Material by Reduction Diffusion Process

摘要

Thermal decomposition process was applied to synthesize Fe_3O_4 and Nd_2Fe_(14)B nanoparticles which were prepared by reduction diffusion process for preparing exchange-coupled nanoparticles. The magnetic Nd_2Fe_(14)B nanoparticles used in this study as the starting materials were synthesized via metal oleate complex method. Also mechanical ball mill technique was applied to the mixture of magnetic Nd_2Fe_(14)B and alpha-Fe nanoparticles to build an exchange-coupled nanoparticle. The mixture of Nd_2Fe_(14)B/alpha-Fe of nanoparticle was confirmed by transmission electron microscopy (TEM). The crystal structure of nanoparticle was characterized by X-ray diffraction pattern (XRD). The magnetic properties were characterized with saturation magnetization from hysteresis loop by vibrating sample magnetometer (VSM). Thermogravimetry using a microbalance with magnetic field gradient positioned below the sample was used for the measurement of a thermomagnetic analysis (TMA) curve showing the downward magnetic force versus temperature.