MEAM Ph.D. Thesis Defense: “Bio-inspired Architected Materials/structures with Enhanced Failure Characteristics”

Structural failure is a critically important design consideration in many engineering applications. Nature provides a number of interesting examples of lightweight structural features that exhibit outstanding failure characteristics. Recent progress in additive manufacturing has facilitated precise control over geometric features, allowing for the implementation of bio-inspired structural designs on a layer-by-layer basis. In this thesis, we will introduce the role of geometry in the failure characteristics of bio-inspired architected materials/structures together with a new bio-mimic manufacturing method designed for these bio-inspired architected materials/structures. We will first present the use of bamboo-inspired void patterns to geometrically improve the failure properties of structures made from brittle polymers under flexural bending. Then, we will extend this study into a material system with tunable plasticity to study the effect of plasticity on the fracture behavior of different architected voids. Lastly, we will showcase the concept of employing simulated “swarms” of bio-inspired agents, such as those mimicking the behavior of bees and ants, to create novel designs of architected materials/structures that exhibit enhanced fracture properties, including improved energy dissipation to failure and damage tolerance under complex loading conditions.