Kinetic Monte Carlo simulation of ZrO2 coating deposited by EB‐PVD

Abstract

AbstractKinetic Monte Carlo (KMC) simulations have been used for electron beam physical vapor deposition (EB‐PVD) of ZrO2 coatings, with the critical potential function fitted by full first‐principles calculations in the framework of density functional theory, emphasizing the effect of critical processing parameters, for example, the substrate temperature (600–1150 K), deposition rate (0.03–7.5 μm/min), and initial kinetic energy (0–0.5 eV). Here, the interaction between ZrO2 particles is described by coarse grain (CG) model with a numerical non‐bonded potential developed by multi‐iterative boltzmann inversion (multi‐IBI). Overall, the calculated energy barrier by the nudged elastic band (NEB) shows the internal diffusion (3.29–4.80 eV) requires more energy than the surface diffusion (2.90–3.42 eV), because of fewer surrounding particles in the latter. Moreover, the energy barrier of Line Jump is smaller than that of Schwoebel Jump, contributing to the columnar grains rather than a dense coating. Of importance, the simulated morphologies of ZrO2 coatings are well consistent to experiments, with a weaker effect from the substrate temperature, initial kinetic energy to deposition rate. Furthermore, the porosity can be effectively reduced by increasing the temperature and initial kinetic energy, however, with a slight increase when increasing the deposition rate.