open access

https://hdl.handle.net/2115/38862

Self-ignition combustion synthesis of TiFe in hydrogen atmosphere

英語

Metal hydrides

2009-07-08

Elsevier B.V.

Journal of Alloys and Compounds

480(2)

592-595

This paper describes the self-ignition combustion synthesis (SICS) of highly active titanium iron (TiFe) in a high-pressure hydrogen atmosphere without employing an activation process. In the experiments, well-mixed powders of Ti and Fe in the molar ratio of 1:1 are uniformly heated up to 1085℃, the eutectic temperature of Ti-Fe binary system, in pressurized hydrogen at 1.0 MPa. The electric source is disconnected immediately after the ignition between Ti and Fe, and the mixture is cooled naturally. In the experiments, the exothermic reaction Ti + Fe → TiFe + 40 kJ occurrs at 1085℃ after the hydrogenation and decomposition of Ti. X-ray diffraction analysis showes that the final product had only one phase -- TiFeH_[0.06] -- which contains 1.55 mass% of hydrogen at 4.0 MPa of hydrogen pressure. The product obtained by SICS contains considerably more hydrogen quickly as compared to the commercially available product; this fact can be explained by the porous structure of the obtained product, which is observed using a scanning electron microscope. In conclusion, the SICS of TiFe saves time and energy, yields products with high porosity and small crystals, enabled easy hydrogenation, and did not require activation processes.

学術雑誌論文

Accepted Manuscript

0925-8388