No abstract

We report a systematic study of the effects of a 400 keV helium ion beam irradiation on the surface morphology and crystal structure of Ti 3 AlC 2 by combined scanning electron microscopy, grazing incidence X-ray diffraction and transmission electron microscopy. Helium irradiation experiments were performed at both room temperature and 500 o C, respectively, with fluence up to 2.0 × 10 17 He + /cm 2. After irradiation, intragranular orientated cracks grew along the (10 1 0) Ti3AlC2 plane and the surface has started to exfoliate. The formation of the cracks is mainly attributed to the reduction of the lattice parameter along the a direction induced by ion irradiation, and the crack growth is affected by the grain size and the content of impurity phase TiAl 3. The surface exfoliation is due to the blistering of He bubbles at the projected depth.