Alloy 33 is a candidate alloy for accident tolerant fuel cladding due to its good corrosion resistance and low reactivity compared to zirconium alloys. The effect of irradiation on stress corrosion cracking (SCC) behavior of Alloy 33 was evaluated using irradiation with 2 Me protons to 5 dpa at 360°C. The hardness increased from 287 HV in the un-irradiated condition to 567 HV (97% increase) in the irradiated condition. Stress corrosion cracking behavior was evaluated in a simulated boiling water reactor (BWR) environment under normal water chemistry (NWC) using constant extension rate tensile (CERT) test in which samples were strained up to 6% at a strain rate of 3×10~(-7) s~(-1) at 288 °C. Scanning electron microscopy (SEM) after the test revealed intergranular cracking in the irradiated region but not in the un-irradiated region. Dislocation channels were observed in the irradiated region, which were absent in the un-irradiated region. However, several ruptures of the oxide film were observed in the un-irradiated region, but not in the irradiated region. Raman analysis of the irradiated as well as un-irradiated zones indicated that the oxide-film consisted mainly of NiFe_2O_4 and FeCr_2O_4 No qualitative difference in the oxide firm was detected between the un-irradiated and irradiated zones.
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