I-Corps: Auxetic Structures for Practical Applications

I-Corps：实际应用的拉胀结构

• 批准号: 1648690
• 负责人: Lesley Berhan
• 金额: $ 5万
• 依托单位: University of Toledo
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-15 至 2017-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1648690&HistoricalAwards=false
• 关键词: Corps; Auxetic; Structures; Practical; Applications

The broader impact/commercial potential of this I-Corps project lies in the contribution of a framework for the development of auxetic composites that are suitable for a broad range of applications (an auxetic material, when stretched along its length, becomes thicker in width-wise directions and it becomes thinner when compressed lengthwise). This project has the potential to be pivotal in the way that auxetic materials are studied, designed and fabricated. The commercial potential spans several different industries where improved impact resistance, indentation resistance, energy and sound absorption properties, and synclastic curvature are sought. The greatest commercial impacts will be in applications requiring a combination of these properties, including personal protective equipment, and structural and noise and vibration applications in the automotive and aerospace sectors.This I-Corps project is centered on the development of negative Poisson's ratio (i.e. auxetic) composites for a wide range of commercial applications. The technology is motivated by the many attractive mechanical properties of auxetic materials. In theory, a negative Poisson's ratio material has improved hardness, impact resistance, fracture toughness, sound absorbing properties, and shear modulus over one with a positive Poissons ratio. In addition, auxetic materials exhibit synclastic curvature when bent, which means that they can be bent into a doubly curved shape, thus eliminating some of the machining necessary to fabricate curved or dome-shaped parts. Since most currently available auxetic materials and structures are porous and have low stiffness, practical structural applications remain largely elusive. This project represents a direct route to structures that exploit the benefits of auxetic materials for commercial applications. The uniqueness of the approach lies in the use of origami patterns which exhibit auxetic behavior when folded to inform the design and development of a new class of negative Poisson's ratio structures. Those structures can be realized through folding and/or additive manufacturing, with the material and length scale selection based on the specific application.

该 I-Corps 项目更广泛的影响/商业潜力在于为开发适合广泛应用的拉胀复合材料框架做出了贡献（拉胀材料在沿其长度方向拉伸时，在宽度方向上变得更厚，在纵向压缩时变得更薄）。该项目有可能在拉胀材料的研究、设计和制造方面发挥关键作用。商业潜力跨越多个不同的行业，这些行业寻求改进的抗冲击性、抗压痕性、能量和吸音性能以及同步曲率。最大的商业影响将出现在需要结合这些特性的应用中，包括个人防护设备以及汽车和航空航天领域的结构、噪声和振动应用。该 I-Corps 项目的重点是开发用于广泛商业应用的负泊松比（即拉胀）复合材料。 该技术的灵感来自于拉胀材料的许多有吸引力的机械性能。 理论上，负泊松比材料比正泊松比材料具有更高的硬度、抗冲击性、断裂韧性、吸音性能和剪切模量。 此外，拉胀材料在弯曲时表现出同步曲率，这意味着它们可以弯曲成双弯曲形状，从而消除了制造弯曲或圆顶形零件所需的一些加工。由于目前大多数可用的拉胀材料和结构都是多孔的且刚度较低，因此实际的结构应用在很大程度上仍然难以捉摸。 该项目代表了一条利用拉胀材料的优点进行商业应用的结构的直接途径。该方法的独特之处在于使用折纸图案，折纸图案在折叠时表现出拉胀行为，为新型负泊松比结构的设计和开发提供信息。这些结构可以通过折叠和/或增材制造来实现，并根据具体应用选择材料和长度尺度。