Molecular Dynamics Analysis and Optimization of Ultra-High-Temperature Ceramic (UHTC) Compositions for Propulsion

Author(s):

Robert Slapikas, Anindya Ghoshal, Luis Bravo, Muthuvel Murugan, and Douglas Wolfe

Abstract:

In this project, atomistic simulations were performed to analyze the material properties of ultra-high-temperature ceramics (UHTCs) for their use in aero-propulsion. Through mechanical testing and the use of the Green–Kubo formulation, the mechanical and thermal properties of transition metal borides ZrB₂ and HfB₂ are obtained using the classical molecular dynamics simulations code LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator) and the bond-order Tersoff potential. These results show how the material properties of the UHTCs change with increasing temperature. The surface oxidization of single-crystal and polycrystalline silicon carbide is determined using the ReaxFF reactive interatomic potential. The simulations in this work were performed in the temperature range of 26–2000 °C. The findings from this work evaluate the influence of extreme environments and the volatilization of molecules from the UHTC surface due to oxidization; however, further analysis of the oxidization of UHTCs would need the use of newly parameterized reactive potentials.