Breaking the Surface: Buoyant Metal–Polymer Open–Cell Hybrid Lattice Metamaterials
Abstract
Metallic lattice metamaterials have demonstrated transformative potential across biomedical, aerospace, defense, and thermal engineering. Yet their application in buoyant marine structures has remained elusive, as their open‐cell architectures inherently prevent flotation, even at densities below that of water. Here, we present the first buoyant metal–polymer open‐cell hybrid lattice metamaterial. The design is guided by a novel skeletal density framework, built around an environment‐independent buoyancy parameter that excludes externally accessible porosity. The resulting hybrid architecture combines Ti‐6Al‐4V hollow‐strut lattices (HSLs)—fabricated by laser‐based powder bed fusion (PBF‐LB)—with expandable polyurethane (PU) foam injected into the internal channels of each strut. This architecture retains external open‐cell permeability while achieving skeletal densities below 1.0 g/cm 3 , enabling reliable buoyancy prediction and control. Real‐world applicability is demonstrated using a Ti‑6Al‑4V+PU hybrid buoy that floats stably in natural seawater. This hybrid architecture exhibits higher specific strength than conventional marine materials such as high‑density polyethylene (HDPE) and 316L stainless steel (SS316L). Seawater immersion tests further demonstrate corrosion resistance and water‑exclusion capability. Finite‑element simulations elucidate fracture initiation and predict failure modes consistent with experimental observations. Importantly, these hybrid buoyant architectures preserve flotation even after severe structural damage. This work introduces a new class of buoyant metamaterials and establishes skeletal density as a general design principle for open‑cell structures in targeted liquid media.
Related
- Functional Polymer Nanocomposite Coatings for Naval and Maritime Applications: Advances in Protection, Durability, and Surface Engineering
- Surface-localized thermoresponsive molecularly imprinted polymer for gentamicin recognition and aqueous regeneration
- Instantaneous Mechanical Programming of Polymer Microparticle Shape and Surface Architecture
- BULK VERSUS SURFACE CHARGE RECOMBINATION KINETICS IN POLYMER HETEROJUNCTION NANOPARTICLE PHOTOCATALYST DISPERSIONS
- Bulk versus surface charge recombination kinetics in polymer heterojunction nanoparticle photocatalyst dispersions
BibTeX
@article{noronha2026breaking,
title = {{Breaking the Surface: Buoyant Metal–Polymer Open–Cell Hybrid Lattice Metamaterials}},
author = {Jordan Noronha and Joey Tallon and Raad Omar and Jason Dash and Andrey Molotnikov and Martin Leary and Milan Brandt and Ma Qian},
journal = {Advanced Materials},
year = {2026},
month = aug,
doi = {10.1002/adma.74641},
url = {https://hal.science/hal-05752846v1},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - JOUR
TI - Breaking the Surface: Buoyant Metal–Polymer Open–Cell Hybrid Lattice Metamaterials
AU - Jordan Noronha
AU - Joey Tallon
AU - Raad Omar
AU - Jason Dash
AU - Andrey Molotnikov
AU - Martin Leary
AU - Milan Brandt
AU - Ma Qian
PY - 2026
DA - 2026/08/28
JO - Advanced Materials
DO - 10.1002/adma.74641
UR - https://hal.science/hal-05752846v1
AB - Metallic lattice metamaterials have demonstrated transformative potential across biomedical, aerospace, defense, and thermal engineering. Yet their application in buoyant marine structures has remained elusive, as their open‐cell architectures inherently prevent flotation, even at densities below that of water. Here, we present the first buoyant metal–polymer open‐cell hybrid lattice metamaterial. The design is guided by a novel skeletal density framework, built around an environment‐independent buoyancy parameter that excludes externally accessible porosity. The resulting hybrid architecture combines Ti‐6Al‐4V hollow‐strut lattices (HSLs)—fabricated by laser‐based powder bed fusion (PBF‐LB)—with expandable polyurethane (PU) foam injected into the internal channels of each strut. This architecture retains external open‐cell permeability while achieving skeletal densities below 1.0 g/cm 3 , enabling reliable buoyancy prediction and control. Real‐world applicability is demonstrated using a Ti‑6Al‑4V+PU hybrid buoy that floats stably in natural seawater. This hybrid architecture exhibits higher specific strength than conventional marine materials such as high‑density polyethylene (HDPE) and 316L stainless steel (SS316L). Seawater immersion tests further demonstrate corrosion resistance and water‑exclusion capability. Finite‑element simulations elucidate fracture initiation and predict failure modes consistent with experimental observations. Importantly, these hybrid buoyant architectures preserve flotation even after severe structural damage. This work introduces a new class of buoyant metamaterials and establishes skeletal density as a general design principle for open‑cell structures in targeted liquid media.
SN - 0935-9648
SN - 1521-4095
ER -