Characterisation and Validation of Submicron Structures in a Fe–Al–Nb Alloy Using Inverse Modelling of the

Using conventional matrix correction methods, the spatial resolution of EPMA is limited by the size of the electron interaction volume. Secondary and back-scattered electron imaging techniques achieve higher spatial resolution, but can only provide structural information at the surface of the sample. In this study, we present a method for reconstructing complex three-dimensional material structures in EPMA by means of inverse modelling, based on the deterministic spherical harmonic PN method for simulating electron transport in solids. We apply this approach to characterise submicron structures in an Fe-Al-Nb alloy, where the structural features are smaller than the interaction volume. The accuracy of the reconstructed material structure is further validated by comparing with cross-sectional micro-structural information obtained via FIB/SEM tomography.