Disorder Enhances the Fracture Toughness of Two-Dimensional Mechanical Metamaterials

No Thumbnail Available
Penn collection
School of Engineering and Applied Science::Department of Mechanical Engineering & Applied Mechanics::Departmental Papers (MEAM)
Discipline
Mechanical Engineering
Subject
fracture toughness
disordered materials
Region
Funder
National Science Foundation MRSEC
US Department of Defense NDSEG
Villum Foundations Experiment Programme
Grant number
DMR-1720530
DMR-2309043
Date issued
2025-01-20
Distributor
Scholarly Commons, University of Pennsylvania Libraries
Related resources
Author
Fulco, Sage
Contributor
Budzik, Michal
Xiao, Hongyi
Durian, Douglas
Turner, Kevin
Abstract

Mechanical metamaterials with engineered failure properties typically rely on periodic unit cell geometries or bespoke microstructures to achieve their unique properties. We demonstrate that intelligent use of disorder in metamaterials leads to distributed damage during failure, resulting in enhanced fracture toughness with minimal losses of strength. Toughness depends on the level of disorder, not a specific geometry, and the confined lattices studied exhibit a maximum toughness enhancement at an optimal level of disorder. A mechanics model that relates disorder to toughness without knowledge of the crack path is presented. The model is verified through finite element simulations and experiments utilizing photoelasticity to visualize damage during failure. At the optimal level of disorder, the toughness is more than 2.6 times of an ordered lattice of equivalent density.

Date Range for Data Collection (Start Date)
2023-09-01
Date Range for Data Collection (End Date)
2024-05-01
Digital Object Identifier
Comments
Recommended citation
Collection