Importance of Microstructural Features in Bimodal Structure–Property Linkage

The bimodal structure, one of the various heterogeneous microstructures, has been studied in an attempt to induce desirable strength-ductility synergies. We developed a physical-based constitutive model which represents the deformation mechanism well considering the evolution of geometrically necessary dislocations and statistically stored dislocation densities. Even though there are many complex correlations of grain size, volume fraction, and spatial distribution of coarse grain/fine grain in a bimodal structure, the bimodal structure-property linkage can be explored by adopting microstructure-based finite element method simulations. This work demonstrates that the bimodal microstructure-property linkage can be analyzed quantitatively to facilitate finding optimal heterogeneous equiaxed bimodal structures. Graphical Abstract