Incorporating Semiautomatic Coprecipitation Apparatus and Gas Nitriding for Synthesis of Iron Nitride from Natural Iron Sand

Abstract

This study aimed to synthesize iron nitride (Fe₃N) material using Fe₃O₄ as the starting material. The synthesis process included coprecipitation of natural iron sand and gas nitriding under flowing NH₃ gas. Semiautomatic coprecipitation apparatus was implemented during coprecipitation process, to improve powder yield and reproducibility of Fe₃O₄ nanopowders. The results of XRD and SEM showed that the semiautomatic coprecipitation apparatus could produce consistent product in terms of final quantity and powder morphology. Furthermore, Fe₃N was produced after gas nitriding for different holding times. Iron oxides, Fe₃O₄ and Fe₂O₃, were still detected in the powder, showing that nitriding parameter was insufficient to produce Fe₃N completely. VSM measurement on the final powder showed typical soft magnetic behavior, with maximum saturation magnetization of 17.21 emu/g and coercivity at 0.04 Oe after 6 hours of nitriding. This study provided an alternative method for local soft magnetic composite production using abundant Indonesian resources.