Improved UO2 Parameters for Grain Boundary Energy Interpolation

Efforts have been made to find an interpolary function for the grain boundary (GB) energies of uranium dioxide, based on work done by Bulatov et al.[Acta Mater. 65, 161 (2014)]. This was done using a MATLAB ® script developed by Harbison[B.S. Thesis, Brigham Young University - Idaho (2015)] and Bulatov et al. Molecular dynamics data was collected using the LAMMPS program developed at Sandia National Laboratory. Results for the,, andsymmetric tilt GBs have been collected; additional GBs will be fitted at a later date as the LAMMPS simulations are completed. The new data sets were calculated with an 800 K anneal which allowed the atoms to relax to a lower energy state. An improved fit is found for theset, whereas theandsets show unexpected trends. Further research needs to be done for theandsets to determine why the fitting procedure does not accurately reflect the expected results. Additional research should also be done to determine if outlying data points necessitate fitting additional cusps