Effect of Mo on the phase stability and elastic mechanical properties of Ti-Mo random alloys from ab initio calculations.

摘要: Ti-Mo alloys are promising materials for shape memory and biomedical materials. Whereas, the appearance of metastable ω phase can cause embrittlement destroy effect. In order to avoid phase, effect Mo on temperature dependent lattice parameters, stability elastic mechanical properties β, α, Ti1-x x (x  =  0-2.0) random was systematically investigated by using exact muffin-tin orbitals method in combination with coherent potential approximation. The theoretical predictions parameters good agreement available experiments. Results show that β Ti0.96Mo0.04 almost transform without deformation volume change, which suggests athermal is easier precipitate grow near 4 at.% content alloys. critical competed stabilization at T  =  300 K ~11.2 at.%. Its valence electron concentration 4.224 viewed as a necessary criterion stability. calculations formation energy used explain successfully why partitioning be found Ti0.91Mo0.09 alloy after annealing. Through analysis energy, both addition increasing stabilize phase. calculated Cauchy pressure, Pugh's ratio, Poisson Young's modulus intrinsically brittle has large compared α phases.