钒基固溶体储氢材料弹性性质第一性原理研究

采用基于密度泛函理论的第一性原理赝势平面波方法，计算了（59Cr-41Ti）_100－xV_x（x=5，15，30，60，80，100）六种钒基储氢合金的晶格常数、弹性性质和电子态密度，计算结果与实验值符合较好.发现当x=60时的钒基合金具有较好弹性性质，杨氏模量为14930 GPa，切变模量为5442 GPa及体弹模量为19396 GPa.结合实验循环性能分析认为在吸放氢过程中合金已经发生塑性变形，弹性 关键词： 钒基固溶体 储氢合金材料 密度泛函理论 弹性性质

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

The lattice parameters， elastic properties and electronic density of state of the （59Cr-41Ti）_100－xV_x（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 Y_zz=14930 GPa， shear modulus C^t=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.