Parametric study on the role of energy and mobility on abnormal grain growth in systems undergoing complexion transition

Abstract Despite many decades of research, the exact mechanism contributing to the persistence of abnormal grain growth (AGG) is poorly understood. In many materials, a structural transition at grain boundary (GB), known as complexion transition, has been suggested as a cause of AGG. However, the precise link between complexion transitions and AGG is still unclear and challenging to study experimentally. Recently, we proposed a thermodynamically consistent complexion transition model and using a phase field study we demonstrated persistent AGG induced by the proposed model. Building on our earlier research, this work aims to clarify the relationship between induced grain growth and the underlying complexion transitions. Complexion transitions can be characterized by their type, which is defined by changes in GB properties such as mobility and energy, and their likelihood of occurrence. By systematically varying the type and likelihood of these transitions, we map the development of microstructure and identified the parameter space for occurrence of AGG through two-dimensional phase-field simulations. Quantitative analysis of relative growth of abnormal grains provides valuable insights into the role of complexion transition parameters on AGG. The findings from this study can contribute to a better understanding of the relationship between processing parameters and microstructure during complexion transitions.