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Abstract Recent advances in computational design and 3D printing enable the fabrication of polymer lattices with high strength‐to‐weight ratio and tailored mechanics. To date, 3D lattices composed of monolithic materials have primarily been constructed due to limitations associated with most commercial 3D printing platforms. Here, freeform fabrication of multi‐material polymer lattices via embedded three‐dimensional (EMB3D) printing is demonstrated. An algorithm is developed first that generates print paths for each target lattice based on graph theory. The effects of ink rheology on filamentary printing and the effects of the print path on resultant mechanical properties are then investigated. By co‐printing multiple materials with different mechanical properties, a broad range of periodic and stochastic lattices with tailored mechanical responses can be realized opening new avenues for constructing architected matter.
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Architected Multimaterial Lattices with Thermally Programmable Mechanical Response
Abstract Architected materials typically maintain their properties throughout their lifetime. However, there is growing interest in the design and fabrication of responsive materials with properties that adapt to their environment. Toward this goal, a versatile framework to realize thermally programmable lattice architectures capable of exhibiting a broader range of mechanical responses is reported. The lattices are composed of two polymeric materials with disparate glass transition temperatures, which are deterministically arranged via 3D printing. By tailoring the local composition and structure, architected lattices with tunable stiffness, Poisson's ratio, and deformation modes controlled through changes in the thermal environment are generated. The platform yields lightweight polymer lattices with programmable composition, architecture, and mechanical response.
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- Award ID(s):
- 1922321
- PAR ID:
- 10448029
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 32
- Issue:
- 1
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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