Interatomic Potentials for Ultra High Temperature Ceramics (UHTC): ZrB2 and HfB2

Ultra high temperature ceramics including ZrB2 and HfB2 are characterized by high melting point, good strength, and reasonable oxidation resistance. These materials are of interest for use as sharp leading edges for hypersonic vehicles among other applications. Progress in computational modeling of UHTCs has been limited in part due to the absence of suitable interatomic potentials. We present a Tersoff style parametrization of such potentials for ZrB2 and HfB2 appropriate for atomistic simulations. Parameters are fit to data generated from DFT based ab initio calculations. The accuracy of the potentials is assessed against further ab initio data.