Raman spectroscopy coupled to principal component analysis for studying UO2 nuclear fuels with different grain sizes due to the chromia addition

Current necessities of nuclear power plants have led to increase burn-up the fuel during operation. In this context, some undesirable processes, such as a higher release gaseous fission products, may occur. New UO2-based fuels are being developed by adding doping agents. Chromia (Cr2O3) has proved considerably enhance grain growth sintering, and thus promote retention these products. The study Cr-doped UO2 at in situ conditions would allow testing real performance operating conditions. existence Raman portable instruments makes scenario feasible. But first, measurement protocols need be developed. Therefore, paper, we explore use spectroscopy an approach for analysis effect Cr2O3 addition set UO2Cr2O3 sintered pellets. validity is demonstrated using Principal Component Analysis (PCA). Three Components describe 98.8% total variance data, they related main modes samples. addition, SEM images shown presence bigger precipitates not only when solubility limit Cr3+ exceeded, but also it reached. By XRD, well-known Vegard behavior observed, Cr3+dissolved into matrix found (748±16) ppm particular sintering used.