Popis: |
The effect of Al on the structures and hydrogen storage properties of TiV 0.8- x Cr 1.2 Al x ( x =0, 0.05, 0.1, 0.15, 0.2) alloys was investigated in this paper. Adopting XRD and PCT measurements etc, we have found that all alloys tested possess single phase with bcc structure and dendrite crystals in as-casting. With increasing of Al from 0 to 6.67at%, the alloy lattice parameters increase, the hydrogen absorption and desorption capacities decrease, and forming enthalpy and entropy enhance. The desorption plateau pressures increase with increasing of Al content linearly. The maximum hydrogen capacity is 3.887 wt%, and the effective hydrogen capacity is 2.288 wt% for TiV 0.75 Cr 1.2 Al 0.05 alloy. |