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Lightweight structures with bioinspired metamaterials, with their uniquely engineered properties not found in naturally occurring materials, have garnered significant attention for their potential in various engineering applications. This study explores the mechanical behavior of sandwich plate structures utilizing the Kresling origami pattern, fabricated through a straightforward 3D printing process. By conducting 3-point bending and compression tests, as well as simulations with Abaqus software, the research investigates the distinctive mechanical properties and performance enhancements these origami-inspired structures offer under mechanical loading. This study is noteworthy for being the first to investigate the bending characteristics of sandwich structures utilizing the two cell Kresling pattern or double Kresling, an area that has not been previously explored. Utilizing the Kresling structure in sandwich panels poses a challenge due to its rotational behavior. To address this, we employ a double Kresling pattern, which confines the rotation to the middle layer. This approach ensures that the outer layers remain stable, maintaining the overall integrity of the sandwich panel structure during deformation under mechanical loading. The findings reveal that the 3D-printed Kresling origami core significantly reduces weight while maintaining structural integrity, making it especially beneficial for aerospace engineering, where lightweight yet strong materials are crucial. This research highlights the potential of Kresling-patterned sandwich plates to improve efficiency and performance in supersonic vehicles, providing valuable insights into their structural efficiency and applicability in advanced engineering fields.
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Extra strengthening and work hardening in gradient nanotwinned metals
Gradient structures exist ubiquitously in nature and are increasingly being introduced in engineering. However, understanding structural gradient–related mechanical behaviors in all gradient structures, including those in engineering materials, has been challenging. We explored the mechanical performance of a gradient nanotwinned structure with highly tunable structural gradients in pure copper. A large structural gradient allows for superior work hardening and strength that can exceed those of the strongest component of the gradient structure. We found through systematic experiments and atomistic simulations that this unusual behavior is afforded by a unique patterning of ultrahigh densities of dislocations in the grain interiors. These observations not only shed light on gradient structures, but may also indicate a promising route for improving the mechanical properties of materials through gradient design.
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- Award ID(s):
- 1709318
- PAR ID:
- 10078698
- Publisher / Repository:
- American Association for the Advancement of Science (AAAS)
- Date Published:
- Journal Name:
- Science
- Volume:
- 362
- Issue:
- 6414
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- Article No. eaau1925
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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