Investigation on tensile properties and failure mechanism of Al(111)/Al3Ti(112) interface using the first-principles method

Abstract

The first-principles tensile simulation was carried out to investigate the Al(111)/Al3Ti(112) interface tensile properties and failure mechanism through the calculated tensile stress, deformation energy, bond length, bond angle, lattice constant, and charge distribution. Results showed that the maximum tensile strength of the Al(111)/Al3Ti(112) interface is 14.38 GPa and the deformation energy is mainly absorbed by the interface and Al side. When the tensile strain exceeds 25%, partial Al–Ti and Al–Al chemical bonds at the interface break and the tensile model is destroyed. As a result of the increasing tensile strain, the lattice constant b (the side length along the [010] direction) decreases continuously and rapidly, and electron holes appear in a large area at the interface and sub-interface, which severely weakens the interaction between atoms. These phenomena indicate that the Al/Al3Ti interface and sub-interface are weak links and fail easily.