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.