| Abstract Scope |
Grain boundary mobility controls grain growth, recrystallization, and microstructural stability, but measuring how fast a boundary moves does not fully explain how it moves. In this work, molecular dynamics simulations are used to study temperature-dependent migration of nickel grain boundaries with different crystallographic character, including Σ5 and Σ3 interfaces. Boundary displacement is tracked over time to determine migration behavior, velocity, and mobility under controlled Synthetic driving force conditions. To move beyond velocity measurements, Interfacial Line Defect Analysis is applied to identify the disconnection content of migrating boundaries, including line defect networks, Burgers vectors, and step heights. This approach connects changes in mobility and faceting behavior to the specific interfacial defects active during migration. By comparing different boundary characters, the study reveals how atomic-scale defect pathways influence whether a boundary remains sluggish, migrates continuously, or evolves into faceted morphologies. These results provide a mechanistic view of grain boundary mobility in nickel. |