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Abstract Three-dimensional (3D) printing of metal components through powder bed fusion, material extrusion, and vat photopolymerization, has attracted interest continuously. Particularly, extrusion-based and photopolymerization-based processes employ metal particle-reinforced polymer matrix composites (PMCs) as raw materials. However, the resolution for extrusion-based printing is limited by the speed-accuracy tradeoff. In contrast, photopolymerization-based processes can significantly improve the printing resolution, but the filler loading of the PMC is typically low due to the critical requirement on raw materials’ rheological properties. Herein, we develop a new metal 3D printing strategy by utilizing micro-continuous liquid interface printing (μCLIP) to print PMC resins comprising nanoporous copper (NP-Cu) powders. By balancing the need for higher filler loading and the requirements on rheological properties to enable printability for the μCLIP, the compositions of PMC resin were optimized. In detail, the concentration of the NP-Cu powders in the resins can reach up to 40 wt% without sacrificing the printability and printing speed (10 μm·s−1). After sintering, 3D copper structures with microscale features (470 ± 140 μm in diameter) manifesting an average resistivity of 150 kΩ·mm can be realized. In summary, this new strategy potentially benefits the rapid prototyping of metal components with higher resolution at faster speeds.
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3D Printing of Ionic Liquid Polymer Networks for Stretchable Conductive Sensors
Abstract Stretchable conductive materials have attracted great attention due to their potential applications as strain sensors, wearable electronics, soft robotics, and medical devices. The fabrication of these materials with customized object geometries is desirable, but the methods to achieve them are still highly limited. Additive manufacturing via vat photopolymerization can generate sophisticated object geometries, but there is still a significant need to print with materials that afford improved conductivity, mechanical properties, elastic recovery, and durability. Herein, stretchable strain sensors with a range of 3D printed designs are reported using vat photopolymerization. Ionic liquid resins are optimized for their printability using Sudan‐I as a photoabsorber and used to fabricate 3D objects that are subjected to compression, stretching, and bending loads that are detected as real‐time changes in current. Additionally, the self‐adhesive nature of these materials enables mechanically damaged structures to be mended together to regain its function as a strain sensor. These ionic liquid resins are compatible with commercial 3D printers, which enhances their applicability for on‐demand production of customized devices.
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- Award ID(s):
- 1752972
- PAR ID:
- 10421050
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 8
- Issue:
- 23
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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