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Abstract Failure of materials and structures is inherently linked to localized mechanisms, from shear banding in metals, to crack propagation in ceramics and collapse of space‐trusses after buckling of individual struts. In lightweight structures, localized deformation causes catastrophic failure, limiting their application to small strain regimes. To ensure robustness under real‐world nonlinear loading scenarios, overdesigned linear‐elastic constructions are adopted. Here, the concept of delocalized deformation as a pathway to failure‐resistant structures and materials is introduced. Space‐tileable tensegrity metamaterials achieving delocalized deformation via the discontinuity of their compression members are presented. Unprecedented failure resistance is shown, with up to 25‐fold enhancement in deformability and orders of magnitude increased energy absorption capability without failure over same‐strength state‐of‐the‐art lattice architectures. This study provides important groundwork for design of superior engineering systems, from reusable impact protection systems to adaptive load‐bearing structures.
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This content will become publicly available on June 1, 2026
Functionally graded spinodal nanoarchitected ceramics with unprecedented recoverability
A fundamental challenge for lightweight architected materials is their propensity for localized failure due to layered buckling, plastic shear-banding or fracture. Recent research efforts have used disorder to interrupt localization and enhance deformation, but most design strategies simply distribute the accumulation of damage, they do not prevent it from developing and propagating. This work explores how gradient architecture can be designed to hinder crack propagation and promote recoverability in nanostructured ceramic metamaterials. We experimentally and numerically investigated five different shell-based spinodal ceramic nanoarchitectures with 10-80 nm thick alumina films. These were fabricated using atomic layer deposition on sacrificial polymeric scaffolds written using two-photon lithography. All thin-walled (<40 nm) architectures underwent shell buckling-dominated deformation and showed nearly full recovery after compression to 45% strain, an expected result for this class of nanoarchitected materials. Thick-walled (>40 nm) isotropic and anisotropic architectures experienced considerable local damage during compression and predictably showed permanent failure even at low strains. Unexpectedly, thick-walled conch-shell inspired gradient architectures showed localized damage but experienced a full recovery after compression to 45% strain. This degree of recoverability has never been observed in this high density of a nanostructured ceramic, particularly one with visible local cracking during compression. This result stems from the length scale of the structural heterogeneity - the gradient layers were sufficiently small so as to inhibit the local damage development needed for crack propagation, thereby preventing catastrophic failure. Our findings have significant implications for how length scales and heterogeneity can be used to design failure-resistant materials from brittle constituents.
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- Award ID(s):
- 2339197
- PAR ID:
- 10610146
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- International Journal of Mechanical Sciences
- ISSN:
- 0020-7403
- Page Range / eLocation ID:
- 110453
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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