Anisotropy

Poisson's ratio

Shear modulus

Bulk modulus

Statistics

Materials science

Density functional theory

Poisson distribution

Cubic crystal system

Thermodynamics

Physics

Mathematics

Optics

Condensed matter physics

Computational chemistry

Elastic modulus

Young's modulus

Composite material

Debye model

Chemistry

Modulus

Crystals

Ni3Al-based superalloys have excellent mechanical properties which have been widely used in civilian and military fields. In this study, the mechanical properties of the face-centred cubic structure Ni3Al were investigated by a first principles study based on density functional theory (DFT), and the generalized gradient approximation (GGA) was used as the exchange-correlation function. The bulk modulus, Young’s modulus, shear modulus and Poisson’s ratio of Ni3Al polycrystal were calculated by Voigt-Reuss approximation method, which are in good agreement with the existing experimental values. Moreover, directional dependences of bulk modulus, Young’s modulus, shear modulus and Poisson’s ratio of Ni3Al single crystal were explored. In addition, the thermodynamic properties (e.g., Debye temperature) of Ni3Al were investigated based on the calculated elastic constants, indicating an improved accuracy in this study, verified with a small deviation from the previous experimental value.

The Mechanical Properties and Elastic Anisotropies of Cubic Ni3Al from First Principles Calculations