Hydrogen Reduction of Fe_2O_3/WO_3 Mixture with Synthesis of Nanocrystalline Fe/W Composite
Access this Article
Search this Article
Nanocrystalline Fe-W composite is synthesized through the reduction of iron oxide/tungsten oxide (Fe<SUB>2</SUB>O<SUB>3</SUB>/WO<SUB>3</SUB>) mixture with pure hydrogen gas at 700–1000°C. AR grade Fe<SUB>2</SUB>O<SUB>3</SUB> and WO<SUB>3</SUB> powders were mixed thoroughly in ball mill and compacted. The dried compacts were isothermally reduced in pure hydrogen at 700, 800, 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 XRD, SEM, VSM and reflected light microscope to reveal the effect of hydrogen reduction on microstructure, magnetic properties and reaction kinetics of produced Fe-W composite. Complete reduction was achieved with the synthesis of nanocrystalline (36.3 nm) homogenous Fe-W composite. Arrhenius equation with the approved mathematical formulations for the gas solid reaction was applied for the calculation of the activation energy values and detecting the controlling reaction mechanism.
- Materials Transactions, JIM
Materials Transactions, JIM 49(6), 1480-1485, 2008-06-01
The Japan Institute of Metals and Materials