Unravelling the threshold displacement energy of TaC using ab initio molecular dynamics simulation

The threshold displacement energy ( E d ) determines the quantity of defects generated through the minimum kinetic energy of a particle. Here, the displacement process of TaC is studied and hence the E d is determined utilizing the ab-initio molecular dynamics simulation method. We use seven different crystallographic orientations, namely [100], [110], [111], [210], [211], [221], and [321] to observe the interaction between the primary knock-on atoms (PKAs) for both Ta and C. The computation of E d values is taken between 16 eV and 50 eV. The weighted average E d values are calculated from PKA orientations, which are found to be 42 eV for the Ta atom and 26 eV for the C atom. For Ta PKAs, anti-site defects are developed; however, they are not observed in the case of C PKAs. The collision mechanism is primarily influenced by the consecutive replacement collisions occurring along the [110] atomic row, resulting in a reduction of the E d value in the crystallographic orientations. Finally, it is found that the E d values play the role of creating the interstitial defects in the TaC.