Auxetic behavior from rotating triangles

  title={Auxetic behavior from rotating triangles},
  author={Joseph N. Grima and Kenneth E. Evans},
  journal={Journal of Materials Science},
Materials with a negative Poisson’s ratio (auxetic) exhibit the very unusual property of becoming wider when stretched and narrower when compressed [1]. This property gives a material several beneficial effects such as increased shear stiffness, increased plane strain fracture toughness, increased indentation resistance and improved acoustic damping properties [1–5]. In recent years several auxetics have been manufactured by modifying the microstructure of existing materials, including foams [2… 

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