Hydrogen isotopes mobility and trapping in VCrTi alloys

Theoretical calculation for the phonon spectrum and thermodynamic functions of vanadium and its hydride

“…Vanadium is an excellent material favored by people because of its hard texture, high temperature resistance, low specific gravity, high strength and stable chemical properties, as an advanced hydrogen storage material, vanadium-based hydrogen storage alloys have a broad application prospect in national defense and civil industry. In recent years, many scholars have made researches on them, Budylkin et al [1] have studied the behavior of hydrogen isotopes in V-Cr-Ti alloys, this material has been successfully applied to the treatment of hydrogen isotopes in fusion reactors; the "trap" effect of H in V has been studied by Arbuzov et al [2] , the hydrogen absorption and desorption behavior of vanadium and vanadium-based alloys with cubic centers have been studied by Libowitz et al [3] . The behavior of dissolved hydrogen in alloys such as V-Nb and V-CR was studied by Stephen [4] ; the vanadium-based BCC alloys can react rapidly with hydrogen without activation at room temperature was studied by Maeland et al [5,6] In this paper, the lattice structure and energy of Vanadium and vanadium hydrides are calculated respectively by using the Density Functional theory method, and the density functional perturbation theory (DFPT) method is used, the densities of phonon states of vanadium and vanadium hydrides and their thermodynamic functions such as heat capacity, entropy, Helmholtz free energy and Gibbs Free Energy at 298.15 K are calculated.…”