The evolution of irradiation defects and hardening of CVD-SiC induced by He ions irradiation at 800°C

In this study, 500 keV He ions were used to irradiate CVD-SiC samples at 800 °C. The influence of doses on the microstructural evolution and hardness of the irradiated samples were investigated by TEM, Raman, and nanoindentation. TEM results show that He bubbles and dislocation loops appeared after irradiation, and their number densities increased with doses, resulting in the gradual decrease of the intensity of the TO peak in Raman spectra. Moreover, He platelets with strain field were observed in both stacking faults and matrixes. Nanoindentation results indicated that the irradiation hardening occurred, and the hardening degree was positively correlated with the irradiation dose.