Abstract The Whole Powder Pattern Modelling (WPPM) approach of diffraction line profile analysis (LPA) was applied for the first time on PuO2 in order to understand the evolution of the microstructural properties as a function of process conditions. Crystallite size distributions and defect concentrations were determined by WPPM on three different PuO2 samples - including one with a bimodal distribution and compared to the result of more common LPA analyses used in PuO2 literature studies (e.g. Scherrer equation, double Voigt method). The conclusion was that a lognormal distribution of spherical crystallites with dislocations most closely represent the microstructure of PuO2 produced by heating Pu2(C2O4)3(H2O)6•3H2O between 650°C and 850°C. The volume-weighted mean column length (Lvol) parameter obtained from the double Voigt method for the monomodal samples were the same as the Lvol obtained from the WPPM within uncertainty. The two LPA methods did not agree on the Lvol parameters of the bimodal distribution sample with only the WPPM getting values that were consistent with the individual components. The WPPM can potentially provide more insight into future studies of the influences on the microstructure properties of PuO2
Revised: December 8, 2020 |
Published: September 30, 2020