Reduction investigation of WO3/NiO/Fe2O3 and synthesis of nanocrystalline ternary W–Ni–Fe alloy

Nanocrystalline 90% W–7% Ni–3% Fe alloy is synthesized through the gaseous reduction of WO3/NiO/Fe2O3 mixture with pure hydrogen gas at 800–1000 °C. AR grade NiO, Fe2O3 and WO3 powder was mixed thoroughly in ball mill and compacted. The dried compacts were isothermally reduced in pure hydrogen at 800, 850, 900 and 1000 °C. Based on thermogravimetric analysis, the reduction behavior and kinetics reaction mechanism were studied. The initial oxides mixture and the various reduction products were characterized by X-ray Diffractometer (XRD), scanning electron microscope (SEM) and vibrating sample magnet (VSM) to reveal the effect of hydrogen reduction on microstructure, magnetic properties and reaction kinetics of produced W–Ni–Fe alloy. Complete reduction was achieved with synthesis of homogenous nanocrystalline W–Ni–Fe alloy. Arrhenius equation with the approved mathematical formulations for the gas solid reaction was applied for the calculation of the activation energy (Ea) values and detecting the controlling reaction mechanism.