Effect of alloying on elastic properties of ternary Ni-Al-Ti system: Experimental validation

Using combustion synthesis approach we fabricated B2 NiAl intermetallic compound as well as quasi-binary Ni(Al50Ti50) alloy, where half Al atoms are randomly substituted by transitional metal Ti. Young's modulus for synthesized materials was measured and appeared to be 222 ± 10 GPa for NiAl and 175 ± 15 GPa for Ni(Al50Ti50) phases. Using first-principles simulations in the framework of the Density Functional Theory, we investigate the elastic properties of Ni(Al1−xTix) system, including single-crystal, as well as polycrystalline elastic moduli. Direct comparison of the experimental and theoretical values of the Young's modulus demonstrates that the employed theoretical approach allows carefully predict elastic properties of NiAl-based intermetallics. In particular, we predict that alloying NiAl with Ti should increase the ductility of the intermetallic phase.