Preparation of Iron Nitride Material from Natural Iron Sand

Abstract

Iron nitride is a promising material for soft magnetic composite. In the current research, iron nitride compound was produced from natural iron sand, involving coprecipitation and gas nitriding. Prior to coprecipitation, natural iron sands were separated magnetically to obtain pure Fe3O4. Afterward, the coprecipitation was carried out to obtain nanosized Fe3O4. Gas nitriding of Fe3O4 powders was performed at different temperatures i.e. 500 °C, 600 °C and 700 °C, under flowing NH3 gas. Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) are used to investigate the phases obtained after the nitriding process. XRD patterns of the resulted powder indicate that nitriding temperature at 600 °C and 700 °C can produce iron nitride material, i.e. ε-Fe3N. While nitriding temperature of 500 °C is not able to yield iron nitrides. SEM examination reveals that the ε-Fe3N has irregular lamellar morphology. Some impurities are still detected, in the form of Fe3O4, Fe2O3, Ti2O3 and TiO2. Further works regarding the examination of the magnetic properties of the powders will be carried out.