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This study investigates a neoteric approach in manufacturing lunar regolith-filled shape memory vitrimer (SMV) composites for extraterrestrial applications. A SMV with robust mechanical properties was combined with locally available lunar regolith to form a composite material. Fourier Transfer Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), Thermogravimetric Analysis (TGA), and X-ray fluorescence (XRF) were used to characterize the resin, the regolith simulant, and the prepared SMV-regolith composites. We explored conventional synthesis as well as 3D printing methods for manufacturing the composite. Glass fabric-reinforced laminated composites were also prepared to evaluate the impact tolerance and damage healing efficiency. Compressive strength, flexural strength, and impact resistance of the composite were tested at both room and elevated temperatures. A compressive strength of 96.0 MPa and 5.4 MPa were recorded for composite with 40 wt% regolith ratio at room and elevated temperatures, respectively. The glass fabric reinforced SMV-regolith laminate exhibited a bending strength of 232.7 MPa, good impact tolerance under low-velocity impact test, and good healing efficiency up to two damage healing cycles. The 3D printed SMV-regolith composite using a liquid crystal display (LCD)-based printer exhibited a good thermomechanical property with a compressive and tensile strength of 139.16 MPa and 13.99 MPa, respectively, and a good shape memory effect. However, the LCD-based printing using vat-photopolymerization limits the size of the printed samples. Nonetheless, this study shows that utilization of regolith to form advanced composite is possible. SMV regolith composite is a promising material for lunar base applications due to its simple manufacturing process, excellent mechanical properties, and low energy consumption.
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Repeated healing of low velocity impact induced damage in orthogrid-stiffened sandwich panel
Herein, we present a new sandwich panel composed of a carbon fiber grid-stiffened shape memory vitrimer (SMV) core. The sandwich panels were fabricated via a pin-guided dry-weaving technology, and their impact responses were evaluated via low-velocity impact testing. The main failure mode observed after the first round of impact was the transverse cracking of the SMV matrix in the sandwich core. The healing efficiency according to the crack initiation energy (CIE) was found to be 76.5% after the first healing cycle. Even after the second healing cycle, the healing efficiency was greater than 72%. From the low-velocity impact tests, reinforcing the pure SMV core with a grid-skeleton enhanced the impact resistance significantly, that is, the crack initiation energy and peak load were increased by 64.0% and 169.0%, respectively. The results also show that smaller bay area leads to higher impact resistance. With the repeated crack healing, increased impact tolerance, and shape memory effect, it is expected that the sandwich panels will have a good possibility for usage in aerospace and automotive applications.
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- PAR ID:
- 10433297
- Publisher / Repository:
- SAGE Publications
- Date Published:
- Journal Name:
- Journal of Composite Materials
- Volume:
- 57
- Issue:
- 23
- ISSN:
- 0021-9983
- Format(s):
- Medium: X Size: p. 3619-3632
- Size(s):
- p. 3619-3632
- Sponsoring Org:
- National Science Foundation
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