Lee Yung, Jang Bongkyun, Song Hyunggwi, Kim Sumin, Kwon Yong Won, Kang Hyun Seok, Kim Min Seong, Park Inkyu, Kim Taek-Soo, Jang Junho, Kim Jae-Hyun, Park Jang-Ung, Bae Byeong-Soo
Wearable Platform Materials Technology Center (WMC), KAIST, Daejeon, 34141, Republic of Korea.
Department of Materials Science and Engineering, KAIST, Daejeon, 34141, Republic of Korea.
Nat Commun. 2024 Aug 21;15(1):7146. doi: 10.1038/s41467-024-51516-1.
Auxetic metamaterials are a unique class of materials or structures with a negative Poisson's ratio and a wide array of functionalities. However, their inherent porosity presents challenges in practical applications. Filling the inherent perforations while preserving their unique auxeticity is difficult because it demands the seamless integration of components that have highly distinct mechanical characteristics. Here we introduce a seamless auxetic substrate film capable of achieving a negative Poisson's ratio of -1, the theoretical limit of isotropic materials. This breakthrough is realized by incorporating a highly rigid auxetic structure reinforced by glass-fabric, with surface-flattening soft elastomers. We effectively optimize the mechanical properties of these components by systematic experimental and theoretical investigations into the effects of relative differences in the moduli of the constituents. Using the developed auxetic film we demonstrate an image distortion-free display having 25 PPI resolution of micro-LEDs that is capable of 25% stretching without performance degradation.
拉胀超材料是一类独特的材料或结构，具有负泊松比和广泛的功能。然而，其固有的孔隙率在实际应用中带来了挑战。填充固有穿孔同时保持其独特的拉胀性很困难，因为这需要无缝集成具有截然不同机械特性的组件。在此，我们引入一种无缝拉胀基底膜，其能够实现-1的负泊松比，这是各向同性材料的理论极限。这一突破是通过将由玻璃纤维增强的高刚性拉胀结构与表面平整的软弹性体相结合来实现的。我们通过对成分模量相对差异影响的系统实验和理论研究，有效优化了这些组件的机械性能。使用所开发的拉胀膜，我们展示了一种无图像失真的显示器，其具有25 PPI分辨率的微型发光二极管，能够在不降低性能的情况下拉伸25%。
