| Abstract Scope |
The properties of oxide materials are significantly influenced by their dynamic behavior under varying conditions such as temperature, stress, and atmosphere. For instance, the mechanical performance of polycrystalline oxides is governed by the interaction among grain boundaries (GBs), dislocations, and cracks. Additionally, the processing of oxides is often affected by ion diffusion at elevated temperatures. Although many atomic-scale studies have been performed to investigate fracture, deformation, and diffusion mechanisms, most of these observations have been static, leaving dynamic processes largely unexplored—particularly at GBs. In this study, in-situ straining experiments were conducted within a (S)TEM on SrTiO₃ and Al₂O₃ bicrystals to investigate deformation and fracture behavior at GBs. To examine ion diffusion along GBs, electron irradiation was applied to promote GB migration in Al₂O₃. Ti-doped Al₂O₃ bicrystals were also used in ex-situ experiments to model the atomic-scale mechanisms of GB diffusion. |