Quantitative Microstructural Analysis by Correlative EPMA/EBSD/BSE Electron Microscopies Applied to Nuclear Ceramic

Electron microscopy maps were acquired in a mixed-oxide nuclear ceramic to probe independently and optimally grain structure [by Electron BackScattered Diffraction (EBSD)], porosity [by high-resolution BackScattered Electron imaging (BSE)], and elemental distributions [by Electron Probe MicroAnalysis (EPMA) in a separate instrument]. The maps were programmatically correlated spatially and integrated into a single multi-dimensional dataset allowing a correlative approach to assess the interdependence of key ceramic microstructural properties. Through the extraction of statistically representative non-random quantitative correlations between grain size, elemental enrichment, and intra-granular porosity that can be related to solid-state processes, the potency of the method is illustrated. The multi-layered hybrid maps produced by fusing data from the different acquisitions offer novel and unique insights into contiguous crystallographic, microstructural, and chemical features.