Simple strategy toward tailoring fracture properties of brittle architected materials

Based on standard stiffness (compliance) and stress designs in structural topology optimization (TO), this work proposes a simple strategy to tailor fracture properties of brittle architected materials. Material distribution in the design domain is customized through a stress-constrained strain-energy maximization TO framework. Structures consisting of a single (Formula presented.) phase brittle material are studied. Mechanical fracture properties of the optimized structure including stiffness, toughness, strength, and failure displacement are thereafter quantified via the phase field modeling. Reported results show that the obtained architecture can achieve 6 times tougher and more than 1.5 times stronger compared with the stiffness-only TO result. Against to stress-only optimization, all concerned mechanical properties including stiffness, toughness, and strength can be improved by more than 15% simultaneously.