BCC结构TiCrTaV合金的电子结构及力学性能的第一性原理计算

利用基于密度泛函理论的第一性原理方法计算TiCrTaV多组元合金中两种BCC结构的结构稳定性、力学性能、德拜温度、电子结构和布居分析. 生成焓和内聚能结果表明BCC1的结构稳定性更好，更容易形成. 弹性常数和模量表明BCC1的强度和韧性更强，BCC2的抗剪切能力和刚度更好，两种结构均具有弹性各向异性. 德拜温度和Grüneisen参数结果表明BCC2的键合强度和热稳定性更好. 电子结构和布居分析表明两种结构均包含共价键和金属键. Ta原子形成的共价键强度更大，金属键仅存在于Ti、Cr和V原子之间. 元素成键后Ti和V原子失去电子，Cr和Ta原子得到电子.

First-principles calculations on electronic structures and mechanical properties of TiCrTaV alloys with BCC structures

The structural stabilities, mechanical properties, Debye temperatures, electronic structures and population analysis of the BCC1 and BBC2 structures in TiCrTaV multi-component alloys are calculated using the first-principles method based on density functional theory. The formation enthalpy and cohesion energy indicate that BCC1 structure has better structural stability and stronger formation ability. The elastic constants and modulus indicate that the strength and toughness of BCC1 are better, while the shear resistance and stiffness of BCC2 are better. Both structures have elastic anisotropy. Debye temperature and Gruneisen parameters show that BCC2 has better bonding strength and thermal stability. Electronic structure and population analysis show that both phases contain covalent and metallic bonds. The covalent bonds formed by Ta atoms are stronger, and the metallic bonds exist only between Ti, Cr and V atoms. When the elements bond, Ti and V lose electrons and Cr and Ta obtain electrons.