Narrow Results

We employed a first-principles method based on the density functional theory to investigate the effect of impurity O on the site preference and elastic properties of α₂-Ti₃Al. We found that the O atom prefers to occupy the Ti-rich octahedral interstitial site in α₂-Ti₃Al. We calculated the elastic constants of α₂-Ti₃Al with single O atom, which demonstrate that the O presence has no large effect on α₂-Ti₃Al according to the empirical criterions. Other factors such as O cluster should be taken into account to understand the deleterious effect of O on α₂-Ti₃Al. Our results provide a useful reference to further study the mechanical properties of TiAl alloys.