  The elastic properties of paramagnetic cubic B1 (c-) Cr1-xAlxN ternary alloys
are studied using stress-strain and energy-strain methods within the framework
of Density Functional Theory (DFT). A strong compositional dependence of the
elastic properties is predicted. Young's modulus, E, and shear modulus, G,
exhibit the same compositional trends as experimentally measured hardness
values (i.e. increasing with Al content), while bulk modulus, B, remains almost
constant. The isotropic elastic response in the c-Cr1-xAlxN is predicted for
concentrations around x=0.50. Brittle behavior and directional bonding
characteristics are predominant in the c-Cr1-xAlxN coatings in the whole
composition range, and become more pronounced with increasing Al content.
