Effects of He irradiation on Ti3AlC2: Damage evolution and behavior of He bubbles

In present investigation, Ti3AlC2 ceramic was irradiated at room temperature using 50 keV He ions with doses ranging from 8 × 1016 cm−2 to 1 × 1018 cm−2 and the corresponding peak values of dpa varying from 4 to 52. The damage evolution of nanolaminated crystalline structure as well as the formation and the growth of He bubbles induced by He irradiation were investigated by grazing incidence X-ray diffraction (GIXRD), atomic force microscope (AFM) and transmission electron microscopy (TEM). GIXRD analysis showed serious structural disorder but no obvious amorphization even at the highest dose, which was consistent with the selected area electron diffraction (SAED) results. AFM results demonstrated that serious blistering and exfoliation appeared on the surfaces at high doses. TEM observations revealed the formation of spherical He bubbles, string-like bubbles and “faulting zones” at various doses respectively.