First-principles studies of the structural, elastic, electronic and thermal properties of γ′-Ni3Ti

The structural, elastic and electronic properties of ordered face-centered cubic (L12) γ′-Ni3Ti were studied using the projector-augmented-wave (PAW) method within the generalized gradient approximation (GGA). The fact that the elastic constants meet the requirements of mechanical stability for a cubic crystal indicates that γ′-Ni3Ti is mechanically stable at 0 K. The bulk modulus, shear modulus, Young's modulus and Poisson's ratio are estimated from the calculated elastic constants of single crystal. The ratio of the bulk modulus to shear modulus (B/G) is 2.00 and the material is ductile. Through the quasi-harmonic Debye model, the pressure and temperature dependences of the linear expansion coefficient, bulk modulus, the Debye temperature and heat capacity have been investigated for the first time.