The damage evolution of He irradiation on Ti3SiC2 as a function of annealing temperature

The radiation damage response of Ti3SiC2 irradiated by 110 keV helium ions at room temperature (RT), the subsequent evolution of damage including helium bubble growth as a function of annealing temperatures are investigated using grazing incidence X-ray diffraction (GIXRD), Raman spectroscopy and transmission electronic microscopy (TEM). In addition to collision cascade effects leading to TiC nanocrystal formation near the surface of Ti3SiC2, He ion irradiation produces damage due to the growth of He bubbles, which cause a structural transformation into a large grain TiC crystalline phase at high temperatures. The displacement of matrix Si atoms adjacent to the He bubbles along the Si layer in Ti3SiC2 either via bubble growth or the production of inter-bubble fracture is the reason for the structural transformation. Depending on the He damage level, a significant recovery of the He irradiation damage can occur at moderate temperatures. This property may play a positive role in the damage resistance of Ti3SiC2, making it a potential candidate for future nuclear reactor applications.