Microstructural Optimization of Alloys Using a Genetic Algorithm

A methodology is presented to tailor the microstructure of alloys for developing “materials by design.” Theoretical and phenomenological models are used to correlate the microstructure to macroscopic properties, and a genetic algorithm (GA) is used to synthesize the optimal microstructure for satisfying user-defined design requirements. Simulated results are presented for an Al-Mg-Sc-Zr alloy considering low temperature strength, ductility, and high temperature strength as the macroscopic properties of interest. The efficacy of the optimization scheme is also evaluated by comparing the GA results with the global optimal values obtained by searching the entire solution space. The results presented show that the methodology lends itself well to realize the concept of “materials by design.