Principal Investigator C Cem Tasan
Project Website http://tasan.mit.edu/
Professor Taşan's Group develops in-situ microscopy techniques to understand the beautiful but complex physics of microstructure evolution and damage in metallic materials, using this knowledge to design novel nanostructured alloys with excellent damage-resistance and/or healing capabilities.
Research activities in Taşan Group are following three main directions listed below, that address Methods, Mechanisms and Materials, respectively:
(*) Methods: We continuously develop and expand our high resolution multi-probe multi-field mapping method. This approach relies on in-situ SEM (thermo-)mechanical tests accompanied by in-lens SE, EBSD, ECCI, EDX, DIC analyses and crystal-plasticity simulations. It enables mapping of all critical constituents and fields associated with the deformation of multi-phase materials (e.g. microstructural strains, stresses, phase fractions, dislocation densities, damage incidents, crystallographic texture, etc.) at high spatial resolution.
(*) Mechanisms: Employing multi-field mapping methods, we investigate the underlying physical mechanisms of microstructural transformation, plasticity, damage and healing processes in nanostructured multi-phase alloys. Micro-processes of interest include dislocation interactions, mechanical twinning, mechanically-induced martensitic transformation, nano-precipitation, damage nucleation, growth and coalescence, crack closure or blunting, interstitial segregation or diffusion, etc.
(*) Materials: With the improved understanding of critical microstructural mechanisms, we design novel alloys that have properties superior than those of existing materials. Of specific interest is to design damage-resistant and/or healable microstructure design concepts, which would enable efficient re-use strategies to be realized, reducing carbon dioxide emissions associated with materials production. Recent examples of designed materials include metastable dual-phase high entropy alloys, TRIP-Maraging steels, graded Dual-Phase steels, healable TRIP steels, etc.