Combustion synthesis of TiFe by utilizing magnesiothermic reduction

This paper describes a new method for producing TiFe hydrogen storage alloy through combustion synthesis by utilizing the magnesiothermic reduction reaction. The reaction mechanism and the effects of a gaseous atmosphere and pressure on the purity of TiFe products and their hydrogen storage properties were examined in this study. In the experiments, Fe, TiO2, and Mg were used as raw materials and were mixed in a molar ratio of 1:1:4. The mixture was compacted and then heated in a normal or pressurized atmosphere of hydrogen and argon. Temperature changes with time were measured, and the obtained results indicated that the melting of magnesium triggered the reaction. X-ray diffraction analysis revealed that highly pure TiFe could be synthesized in a pressurized atmosphere, containing both hydrogen and argon. The products synthesized in such a pressurized atmosphere stored approximately 1.0 mass% hydrogen and indicated flat plateaus. The process proposed in this study showed the possibility of being a new attractive production method for TiFe hydrogen storage alloy. (C) 2014 Elsevier B.V. All rights reserved.