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Abstract Nature provides us with a large number of functional material systems consisting of hierarchical structures, where significant variations in dimensions are present. Such hierarchical structures are difficult to build by traditional manufacturing processes due to manufacturing limitations. Nowadays, three-dimensional (3D) objects with complex structures can be built by gradually accumulating in a layer-based additive manufacturing (AM); however, the hierarchical structure measured from macroscale to nanoscale sizes still raises significant challenges to the AM processes, whose manufacturing capability is intrinsically specified within a certain scope. It is desired to develop a multiscale AM process to narrow this gap between scales of feature in hierarchical structures. This research aims to investigate an integration approach to fabricating hierarchical objects that have macro-, micro-, and nano-scales features in an object. Firstly, the process setup and the integrated process of two-photon polymerization (TPP), immersed surface accumulation (ISA), and mask image projection-based stereolithography (MIP-SL) were introduced to address the multiscale fabrication challenge. Then, special hierarchical design and process planning toward integrating multiple printing processes are demonstrated. Lastly, we present two test cases built by our hierarchical printing method to validate the feasibility and efficiency of the proposed multiscale hierarchical printing approach. The results demonstrated the capability of the developed multiscale 3D printing process and showed its future potential in various novel applications, such as optics, microfluidics, cell culture, as well as interface technology.
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Review on 3D Printing of Bioinspired Structures for Surface/Interface Applications
Abstract Natural organisms have evolved a series of versatile functional biomaterials and structures to cope with survival crises in their living environment, exhibiting outstanding properties such as superhydrophobicity, anisotropy, and mechanical reinforcement, which have provided abundant inspiration for the design and fabrication of next‐generation multi‐functional devices. However, the lack of available materials and limitations of traditional manufacturing methods for complex multiscale structures have hindered the progress in bio‐inspired manufacturing of functional structures. As a revolutionary emerging manufacturing technology, additive manufacturing (i.e., 3D printing) offers high design flexibility and manufacturing freedom, providing the potential for the fabrication of intricate, multiscale, hierarchical, and multi‐material structures. Herein, a comprehensive review of current 3D printing of surface/interface structures, covering the applied materials, designs, and functional applications is provided. Several bio‐inspired surface structures that have been created using 3D printing technology are highlighted and categorized based on their specific properties and applications, some properties can be applied to multiple applications. The optimized designs of these 3D‐printed bio‐inspired surfaces offer a promising prospect of low‐cost, high efficiency, and excellent performance. Finally, challenges and opportunities in field of fabricating functional surface/interface with more versatile functional material, refined structural design, and better cost‐effective are discussed.
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- PAR ID:
- 10478607
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 34
- Issue:
- 11
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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