Role of irradiation-induced defects on SiC dissolution in hot water

An enhancement of the dissolution of high-purity 3C-SiC in hot water (320 °C, 20 MPa: relevant to the light-water reactor coolant condition) is demonstrated after 5.1 MeV Si-ion irradiation. Optical spectrometry and Kelvin force microscopy revealed the creation of interband-defect localized states within the bandgap. The dissolution rate was found to be dependent on the irradiation fluence, irradiation-induced volume expansion, and the photoluminescence quenching. An annealing study showed prevention of irradiation-enhanced dissolution with the recovery of most defects. These results show that the dissolution rates of irradiated SiC are increased with the population of irradiation-induced defects.