A channeling study of vacancy - solute atom complexes in irradiated aluminum crystals

The irradiation-induced evolution of vacancy -solute atom complexes in Al-Sn and Al-In crystals was studied by ion channeling. The backscattering yields from host and solute atoms near the (100), (110), (211), and (111) channels were measured in these alloys to determine the positions of the solute atoms in the lattice. During annealing near 200 K following 1He+ irradiation at 35 K, the solute atoms trapped vacancies, thus becoming displaced from substitutional lattice sites into the characteristic interstitial positions (1/3,1/6,1/6)a0, and (1/2,1/2,1/2)a0 surrounded by three, four, and six vacancies, respectively. Subsequent irradiation at 70 K reduced the size of these vacancy clusters. The evolution and the decay of these vacancy -solute atom complexes were measured quantitatively during irradiation and annealing