Micro-Raman analysis of the fuel-cladding interface in a high burnup PWR fuel rod

International audience; New insights on the fuel-cladding bonding layer in high burnup nuclear fuel were obtained using micro-Raman spectroscopy. A specimen was specifically prepared from a fuel rod which had been irradiated to an average burnup of 56 GWd.tU-1 in a pressurized water reactor (PWR). Both inner and outer corrosion scale regions were investigated. A 10-15 et956;m thick zirconia bonding layer between fuel and cladding materials which consisted of three distinct regions was observed. Close to the fuel, tetragonal, then monoclinic zirconia was identified as the main phases. Close to the bonding layer-cladding interface, peculiar Raman signals were observed. Similar signals were ob…