The first-principles calculations are used to investigate the effects on mechanical and electronic properties of Ti-7333 alloy under the tension stress along [001], [100] and [110] directions. First, we study the structure and elastic properties of Ti-7333 alloy with 2, 16, 54 and 128 atoms, finding that the structural parameters of four models are comparative due to the approximate value of c/a and the elastic properties are also similar. Hence, we choose Ti-7333 alloy with 16 atoms to study the effects on mechanical and electronic properties under tension stress along [001], [100] and [110] directions. The changes of independent elastic constants, Debye temperature and anisotropic behavior under different tension stress along all the three directions can reflect that the tensile strength of Ti-7333 alloy may exist between [Formula: see text] and [Formula: see text] GPa and also find that it is easier to change the resistance to deformation of Ti-7333 alloy under the tension stress along [100] direction compared with [001] and [110] directions. What’s more, the calculated mechanical parameters show that the Ti-7333 alloy is brittle and the tendency of variations is small with the increase in tension stress. The effects on electronic properties including metallic and covalent properties are not obvious due to the approximate height of TDOS, pseudogap and charge density.

中文翻译：

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拉伸下 Ti-7333 合金的力学和电子性能：第一性原理计算

第一性原理计算用于研究Ti-7333合金在沿[001]、[100]和[110]方向的拉应力下对力学和电子性能的影响。首先，我们研究了2、16、54和128个原子的Ti-7333合金的组织和弹性性能，发现由于c/a近似值，四种模型的结构参数具有可比性，弹性性能也相似. 因此，我们选择16个原子的Ti-7333合金来研究沿[001]、[100]和[110]方向的拉应力对机械和电子性能的影响。独立弹性常数、德拜温度和不同拉应力下各向异性行为沿三个方向的变化可以反映Ti-7333合金的抗拉强度可能存在于[公式：见正文]和[公式：见正文]GPa，还发现与[001]和[110]方向相比，沿[100]方向的拉应力下Ti-7333合金的抗变形能力更容易改变。此外，计算出的力学参数表明，Ti-7333合金呈脆性状，随着拉应力的增加其变化趋势很小。由于 TDOS 的近似高度、赝能隙和电荷密度，对包括金属和共价特性在内的电子特性的影响并不明显。计算出的力学参数表明，Ti-7333合金呈脆性，随拉应力的增加变化趋势较小。由于 TDOS 的近似高度、赝能隙和电荷密度，对包括金属和共价特性在内的电子特性的影响并不明显。计算出的力学参数表明，Ti-7333合金呈脆性，随拉应力的增加变化趋势较小。由于 TDOS 的近似高度、赝能隙和电荷密度，对包括金属和共价特性在内的电子特性的影响并不明显。