Designing resettable metallic materials through multi-field mapping
Professor C. Cem Tasan
Department of Materials Science and Engineering, Massachusetts Institute of Technology
Metals are poor at self-repair due to the ambient temperature sluggishness of transformations compared to, for example, polymers. On the other hand, they respond well to external repair treatments aimed at macroscopic discontinuities (see, for example, repair of bridge steel cracks, worn turbine blades, forging of casting defects, etc.). This forgiving nature of metals, however, has not been utilized to focus on early stages of microscopic damage nucleation, where preventive healing becomes a more feasible option. The challenge thereof arises due to the complexity of plasticity & damage micro-mechanics, and phase transformation kinetics in multi-phase microstructures. In the Tasan Group, by developing multi-field mapping tools and methods, we improve our understanding of these microstructural processes, and by utilizing this understanding, we design resettable-alloys: alloys where each microstructural constituent has the capability to revert back to its exact pre-deformation state, with feasible resetting treatments. This design-for-reuse approach thus sets the foundations for the introduction of metals that can be used continuously.