Tensile and fracture process of the TiN/VN interface from first principles

We have conducted a comprehensive first-principles investigation of tensile and fracture process of the TiN/VN interface by focusing on the strain-stress relationships, the ideal tensile strength and bonding breaking process. The deformation analysis reveals that all bonds are extended at the initial stage until the critical point of fracture is reached. The fracture occurs between the second and third layers on the VN side in both (111) and (001) interfaces and the interaction of potential bonds of facture weakens gradually with the increment of strain during the tensile process. By using several analytical techniques, we identify a charge transfer in both the TiN and VN layers near to interface at the points of fracture during the tensile process, which plays a crucial role in affecting the fracture process. We further demonstrate that the fracture of the TiN/VN interface occurs within the VN and that adhesion energy cannot be simply used to represent tensile strength.