Simulation of Fracture Dynamics of Two-dimensional Titanium Carbide Ti2C under Different Types of Tensile Loading

Paper presents the results of the in-silico experiments concerning simulation of the tension and failure dynamics of two-dimensional (2D) titanium carbide Ti2C under different types of tensile loading. The behavior of 2D nanosheet was studied within classical molecular dynamics (MD) methods. Two different loading methods, namely axial displacement and uniform tensile strain were considered in experiments. The first loading method consists in a consecutive shift of atoms in the right edge of the sample along the x-axis while atoms in the left edge of the sample are held fixed. The uniform tensile strain was performed by shifting left and right parts of the sample in opposite directions. During the simulations, atomistic configurations of the 2D Ti2C nanosheet at different strain values were built for both loading methods. As it follows from the obtained data, different loading procedures lead to different fracture dynamics and crack formation in the studied sample. As calculated atomistic configurations show, in the case of axial displace-ment the fracture begins from the formation of cracks at the lateral edges of the sample. Cracks appear along the layers of constrained atoms at both fixed and shifted edges of the nanosheet, while at uniform tensile strain Ti2C sample undergoes uniform stretching up to the critical strain where the crack starts to form. The strain-stress curves for both axial displacement and homogenous strain were calculated through the virial theorem. Strain-stress dependencies obtained for different loading procedures for Ti2C sample overlap in the area of elastic deformation. Calculated data also show that plastic deformation and following destruction of the Ti2C sample occur at strain ε ( 0.04 for both methods of loading.