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Abstract Heterogeneous material systems consisting of metallic structures and polymer matrixes are of significance for applications such as integrated circuits, microelectromechanical devices, antennas, sensors, actuators, and metamaterials. Scaly-foot snail which lives in the deep ocean exhibits high strength and temperature resistance due to unique shells made of metal and polymer. Recently, different multi-material structures have been fabricated with metal deposition using multiple manufacturing processes. However, using these complicated hybrid processes is challenging to construct complex 3D structures of heterogeneous material with enhanced properties, high resolution, and time efficiency. Here, we establish a novel manufacturing strategy to build bioinspired hierarchical structures with heterogeneous material systems using electrically assisted stereolithography. The photocurable printing solution that can act as an electrolyte for charge transfer was developed, and the curing characteristic of the printing solution was further investigated. A fundamental understanding of the formation mechanism of metallic structures on the polymer matrix was studied through physics-based multiscale modeling and simulations. The correlation between metallic structures morphology, printing solution properties, and printing process parameters, and their effects in building bioinspired hierarchical structures with heterogeneous materials were identified. Demonstrative test cases were built to verify the printing performance of the proposed approach. This research work will deliver a scalable AM process that can facilitate various interesting applications based on bioinspired heterogeneous material and structures.
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An Investigation of Integrated Multiscale Three-Dimensional Printing for Hierarchical Structures Fabrication
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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- Award ID(s):
- 2114119
- PAR ID:
- 10463924
- Date Published:
- Journal Name:
- Journal of Micro- and Nano-Manufacturing
- Volume:
- 9
- Issue:
- 4
- ISSN:
- 2166-0468
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1115/1.4054317
