Cyclic hydrogen absorption–desorption characteristics of TiCrV and Ti0.8Cr1.2VTi0.8Cr1.2V alloys

The cyclic hydrogen absorption–desorption characteristics of TiCrV and Ti0.8Cr1.2VTi0.8Cr1.2V alloys are investigated. Experimental results show that the cyclic hydrogen capacity increases with increasing hydrogen-desorption temperature for both TiCrV and Ti0.8Cr1.2VTi0.8Cr1.2V alloys. The Ti0.8Cr1.2VTi0.8Cr1.2V and TiCrV alloys can maintain steady cyclic hydrogen capacities of about 2.5 wt% and 2.0 wt%, respectively, even after 15 cycles with hydrogen absorption at 25∘C and hydrogen desorption at 400∘C. The hydrogenation for both TiCrV and Ti0.8Cr1.2VTi0.8Cr1.2V alloys includes the processes of first saturated solid-solution and then forming TiCr1.8H5.3TiCr1.8H5.3 and TiH2TiH2 hydrides. The TiCr1.8H5.3TiCr1.8H5.3 hydride has better reversibility than TiH2TiH2 hydride during the hydrogen absorption–desorption.