A reactive force-field for Zirconium and Hafnium Di-Boride

► Zirconium and Hafnium Di-boride are critical ultra-high temperature materials. ► Applications range from re-entry vehicles, hypersonic flights, etc. ► Finite temperature atomistics simulations are currently not possible. ► We develop interatomic potentials within the ReaxFF framework. ► This will pave the way for also modeling chemical reactions. Zirconium and Hafnium Di-Boride are the two major material systems that are of critical importance for applications in ultra-high temperature environments where both oxidation and mechanical damage mechanisms (such as creep) are operative. Atomistic simulations of these materials at finite temperatures have been hampered due to the unavailability of inter-atomic potentials for the involved elements. In this paper, we present the development of interatomic potentials for both ZrB2 and HfB2 within the ReaxFF framework—thus enabling modeling of chemical reactions. The parameters of the reactive force field are derived by fitting to detailed quantum mechanical simulations of ZrB2 and HfB2 clusters and crystal structures.