The first-principles study on the elasticity of V-based solid solution hydrogen storage materials

Abstract

The lattice parameters， elastic properties and electronic density of state of the （59Cr-41Ti）100－xVx（x=5， 15， 30， 60， 80， 100） V-based solid solution hydrogen storage alloys were calculated using the first-principles plane-wave pseudo-potential method based on the density functional theory， and the calculated results were in agreement with the experimental results. It was found that the V-based alloy x=60 showing better elastic properties， with the Young modulus Yzz=14930 GPa， shear modulus Ct=5442 GPa and bulk elastic modulus B=19396 GPa. By combining the experimental cyclic durability performance， we found plastic deformations occurred in the alloys. Thus， we concluded that the elastic properties were not the primary factor that determines the cyclic durability of the V-based hydrogen storage alloys. The micromechanism of the elastic properties of the impure alloys were also explained with the electronic density of state.