Charge Optimized Many Body (COMB) potentials for simulation of nuclear fuel and clad

Abstract

We briefly outline the Charge Optimized Many Body (COMB) potential formalism, which enables the molecular dynamics simulation of complex materials structures in which multiple types of bonding (metallic, covalent, ionic and secondary bonding) coexist. We illustrate its capabilities to address critical issues in the area of nuclear fuel. In particular, we look at U, UO2 and the process of oxidation of U. Further, we characterize the mechanical behavior of Zr, representing LWR clad, and explore the effects of oxidation and hydridation on the mechanical response and briefly illustrate the capabilities of COMB simulations of corrosion. Finally, we briefly assess the materials fidelity of the COMB approach by examining the COMB description for the Zr-H system.