UO2-GaN composites with enhanced thermomechanical and thermophysical properties: A comprehensive molecular dynamics study

This study presents a thorough molecular dynamics simulation of UO2-GaN composites, focusing on their thermomechanical and thermophysical characteristics over a wide temperature range (300–2500 K). To accurately depict atomic interactions between UO2 and GaN, a hybrid interatomic potential with optimized Lennard-Jones parameters was developed. Analyzed methodically were structural, mechanical, and thermal characteristics including lattice constants, elastic moduli, lattice thermal conductivity, and minimum thermal conductivity. Because of GaN's better phonon transport properties, the results reveal that adding GaN greatly increases the lattice thermal conductivity—up to seven-fold compared to pure UO2. While the composite keeps a melting point near that of UO2, guaranteeing high-temperature stability, mechanical qualities also improve somewhat. Combining structural integrity with outstanding thermal performance, these results establish UO2-GaN composites as interesting candidates for next-generation nuclear fuels. This work can lay the computational foundation for future experimental validation and sophisticated fuel design.