Structure Models of Massively Transformed High Niobium Containing TiAl Alloys

摘要: Ab-initio calculations using the Vienna ab-initio simulation package (VASP) were performed for a high Nb bearing γ TiAl based alloy with composition of Ti-46at.%Al-9at.%Nb in order to evaluate effect on crystal structure. The revealed that upon doping resulting structure can have Ti and atoms Al-sites, which leads reduction c/a ratio tetragonal cell ~1.In contrast, is increased, compared binary phase, if occupy solely sites antisite defects (i.e. Al sublattice) are formed. relaxed models used perform high-resolution transmission electron microscopy (HRTEM) high-angle annular dark field scanning (HAADF-STEM) image simulations. results showed positions should be detectable by these spatial resolution methods, although it might easier HAADF-STEM investigations due stronger dependence signal atomic number Z.