Structural and mechanical properties of Al/TiC interface with vacancies: First-principles study

The adhesion, stability, electronic structure, and ductility of Al/TiC interfaces with Al, Ti, and C vacancies (Alv, Cv and Tiv) are investigated using first-principles calculations. The results show that the adhesion can not be improved significantly by Alv. The adhesion of Al/TiC interfaces with Cv and Tiv are stronger than the clean interface. We find the Al atoms will replace the Tiv in the TiC layer for Ti-site with Tiv. Interestingly, the interface will shift from Ti-site into C-site for 75% Tiv. Furthermore, the results of the generalized stacking fault (GSF) energies show that the preferred slip direction is the (110) direction. Based on the Rice criterion of ductility, it is found that Cv will make the interface more brittle. But the ductility of the Al/TiC interface can be improved by Tiv. The theoretical adhesion of Al/TiC interfaces with Cv is in good agreement with experimental results.(c) 2023 Elsevier B.V. All rights reserved.