Alladi Ramakrishnan Hall

Multiphase-field modelling of microstructural evolution in solid-state system

P G Kubendran Amos

IAM-CMS, Karlsruhe

Efficient devising of any processing technique, that induces desired properties in a material, demands a comprehensive understanding of the associated microstructural evolution. Owing to the intricacies of the microstructures, theoretical studies often accompany experimental works in delineating the observed changes. In a theoretical framework, a microstructural evolution is conventionally perceived by tracking the migrating interface. With increase in the morphological complexity of the evolving structure, the underlying formulation which monitors the interface gets proportionately convoluted. Phase-field technique, on the other hand, renders an efficient alternate for modelling microstructural evolutions by obviating the need for interface tracking. This approach has been extended to model and analyse energy-minimising transformations, like grain growth, in polycrystalline systems. While normal grain growth is primarily governed by curvature-driven migration of the interface, the underpinning mechanism considerably shifts when the grains are no longer homogeneous, but are chemically distinct, and are associated with a constituent phase. In the talk, multiphase-field modelling of microstructural transformation exhibited by such complex polycrystalline systems, wherein grain growth and coarsening occur concurrently, will be discussed.