Preferential formation of Al self-interstitial defects in γ-TiAl under irradiation

Empirical dynamic calculations were used to observe a distinct increase in aluminium interstitial defects compared to titanium interstitial species remaining after a displacement cascade (even though Frenkel formation energies for both species were found to be similar). Thermodynamic data from static ab-initio models support this interesting result. Calculations were then used to determine whether these interstitials are free to move and therefore have the possibility of migrating to a surface where a passive Al2O3 layer can be formed.