2004 年 16 巻 2 号 p. 46-49
The intermetallic TiFe alloy is a hydrogen storage alloy with a high hydrogen storage capacity, 1.8wt%, and a relatively low cost compared with other alloys. However, the TiFe alloy does not easily start to absorb hydrogen because of the presence of a very stable oxide layers covering the alloy surface. In order to activate the alloy, the alloy needs an intensive initial activation process at high temperatures over 720K under high hydrogen pressures over 6.5MPa. In this study, the intermetallic TiFe alloy was successfully prepared by mechanical alloying of Ti and Fe metals. The formed nano-TiFe alloy with a mixture of nano and amorphous structures was found to have a very easy, activation behavior compared with a standard polycrystalline TiFe alloy.