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Abstract High‐performance electrical conductors at higher temperatures are increasingly needed in aerospace, electric vehicles, and military applications. This study develops an innovative multilayered graphene–metal composite conductor, significantly surpassing the maximum temperature limit of conventional copper (≈90 °C for commercial wires). This approach involves integrating fine copper (Cu) wire with functional shells to exploit the high electrical conductivity and chemical inertness of silver (Ag) and graphene (G), as well as excellent anti‐oxidation of nickel (Ni). Three different composite conductors, namely, NiGCu, NiAgCu, and NiAgGCu, are synthesized, characterized, and compared to quantify their overall performance and investigate the functionality of each shell. This work highlights the importance of the G layer. For example, NiAgGCu has 29.3% lower resistivity than NiAgCu, 34% lower resistivity than NiGCu, and 18.7% higher current density limit than NiAgCu after exposure to 550–850 °C. Both molecular dynamics (MD) and finite elements (FE) simulations are performed to reveal the detailed mechanisms of unprecedented thermal stability. These theoretical studies suggest that the embedded continuous graphene layer, even with its unavoidable defects, is attributed to significant performance enhancements up to 850 °C. The results present possible strategies to address current technical bottlenecks for high‐performance electrical conductors in harsh environments.
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High-Toughness Aluminum-N-Doped Polysilicon Wiring for Flexible Electronics
One of the essential requirements of any flexible substrate electronic system is the availability of reliable, high density, fine pitch interconnects between components. In this work, we demonstrate a high-toughness two-layer (aluminum, N-doped polysilicon) composite wiring scheme. The top aluminum layer carries most of the current while the polysilicon underlayer electrically bridges any cracks present on the top aluminum induced by flexing thus maintaining electrical conductivity even at very high stresses. When composite and Al control wires on a flexible tape were subject to 4000 cycles of bending, we observed that Al control wires fracture at a 2.5 mm radius of curvature but the composite wires maintain electrical conduction with an increased resistance.
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- Award ID(s):
- 1932602
- PAR ID:
- 10402732
- Date Published:
- Journal Name:
- 2022 IEEE International Conference on Flexible and Printable Sensors and Systems (FLEPS)
- Page Range / eLocation ID:
- 1 to 4
- 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
- Conference Paper:
- https://doi.org/10.1109/FLEPS53764.2022.9781554
