Elasticity of NixW1−x (x ≤ 0.1875) Alloys from First Principles Calculations

The elastic properties of Ni x W 1− x alloys up to x = 0.1875 have been determined from first principles calculations. We have used stress–strain relationships to calculate the C ij elastic coefficients and the Voigt–Reuss–Hill approximations to determine the bulk and shear moduli of polycrystals. The W alloying increases the compression modulus while the shear modulus remains almost constant. Furthermore, the W alloying has a minor effect on the elastic anisotropy and, therefore, on its contribution to the indentation modulus.