Irradiation-disorder Creation in SrTiO₃

The chemical durability of crystalline matrices loaded with actinides can be stronglyreduced when α-decays generate enough disorder to induce a crystalline to amorphoustransition. The alpha decay of actinides in SrTiO₃ (α-recoils and α-particles) was simulated using Pb and He irradiation. This study shows that the He-ion annealingprocess that operates in some apatitic structure is negligible in SrTiO₃ where thedisorder evolution at room temperature has a strong sigmoid dependence on dose. Thedirect-impact/defect-stimulated model, the cascade quenching/epitaxial recrystallizationmodel, and a direct-impact/cascade-overlap model were used to reproduce the SrTiO₃-disorder evolution under Pb-ion irradiation.