b'Figure 3. a) Cross-section of one of the H-cups. b) High magnification optical microscope image of the fuel-cladding interface.consistent with the correspondingreveal an obvious chemical interaction fission gas release measurements. Thebetween the fuel and the alloy at low large surface-to-volume ratio of theburnup (8.7 GWd/tHM). Similar fuel disks in this configuration couldobservations were made on the other be the factor favoring larger fissioncapsules containing the non-oxidized gas release compared to standard LWRalloy. The optical microscopy analyses fuels irradiated to similar conditions.on the other samples are in progress The pre-existing oxide layer is visibleand will be compared to provide in the micrograph.The thickness isa comprehensive evaluation of the consistent with the measurementsvarious interaction layers.performed pre-irradiation. The morphology of the interface does not 2019|AFC ACCOMPLISHMENTS 107'