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Advances in vat photopolymerization 3D printing have the potential to significantly improve the production of ceramic materials for electrochemical energy devices. Solid oxide fuel cells (SOFCs) and solid oxide electrolysis cells (SOECs) necessitate high‐resolution ceramic manufacturing methods, as well as precisely controlled porosity (≈20–40%) for optimal gas transport. Achieving a balance between this porosity and mechanical integrity, especially under thermal stress, remains a challenge. Herein, the successful fabrication of porous yttria‐stabilized zirconia (YSZ) ceramics using vat photopolymerization 3D printing is demonstrated, achieving porosities ranging from 6% to 40% and corresponding grain sizes of ≈80–550 nm. It is found that 3D‐printed YSZ with ≈33% porosity exhibited a Weibull modulus ofm = 5.3 and a characteristic strength of over 36 MPa. In the investigation, it is further revealed that these ceramics can withstand thermal shock up to 500 °C, retaining over 70% of their flexural strength. This remarkable performance suggests significant potential for 3D‐printed porous YSZ in SOFCs and SOECs, paving the way for potential improved efficiency, reduced fabrication costs, and innovative designs in these next‐generation clean energy technologies.
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Study of Proximity Effect in Projection based Micro Vat Photopolymerization Process
Micro Projection-based Stereolithography (µPSL), also known as micro vat photopolymerization, is a promising technology that could revolutionize microfabrication by providing benefits similar to traditional lithography while reducing production time and cost. However, it faces a significant challenge in the form of the "proximity effect." This effect occurs when adjacent features are too close together, causing undesirable artifacts and limiting the achievable fabrication resolution. The proximity effect is caused by interactions between adjacent pixels of light and affects both the spatial and temporal domains of the fabrication process. Although researchers have been aware of this issue for some time, there has been little progress in understanding and addressing the proximity effect in micro vat photopolymerization. Existing models developed for laser-based systems can explain the effect to some extent, but they do not fully account for the impact of large area projection or explain how local threshold changes affect part size. This research aims to fill this knowledge gap by using in-situ observation systems to experimentally study the spatial and temporal proximity effects in single-shot vat photopolymerization microfabrication. We also investigate the role of oxygen in the proximity effect and lay the groundwork for better understanding how the effect impacts periodic structures with micronic inter-feature distances. In conclusion, while micro vat photopolymerization offers significant advantages over traditional lithography, the proximity effect remains a significant obstacle. This research represents an important step forward in addressing this challenge and improving the accuracy and resolution of vat photopolymerization in microfabrication.
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- Award ID(s):
- 2111056
- PAR ID:
- 10534010
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Additive Manufacturing
- Volume:
- 79
- Issue:
- C
- ISSN:
- 2214-8604
- Page Range / eLocation ID:
- 103926
- 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/10.1016/j.addma.2023.103926
