Molecular dynamics simulation of TiN (001) thin films under indentation

We optimize the second nearest-neighbor modified embedded atom method (2NN MEAM) potential for Ti-N system based on single-element potential of Ti and N. The potential parameters are determined by fitting cohesive energy, lattice parameters, and elastic constants of TiN with a NaCl-type structure. We also conduct MD simulation of indentation on TiN (001), aimed to gain insight into the deformation mechanism at 0 K and 300 K, and analyze in detail the microstructural evolution and bond variation. We demonstrate that the optimized potential can be applied to the Ti-N system with various phases. Moreover, we also find that dislocations and slips are generated from the contact point during indentation, yet are reluctant to migrate. In addition, hardness is found to reduce when temperature rises to room temperature owing to the enhanced migration of slips at high temperature.