Auxetic behavior from rotating squares

  title={Auxetic behavior from rotating squares},
  author={Joseph N. Grima and Kenneth E. Evans},
  journal={Journal of Materials Science Letters},
Auxetic materials exhibit the very unusual properties of becoming wider when stretched and narrower when squashed [1], that is they have negative Poisson’s ratios. Apart from the pure scientific interest of having materials showing such an unconventional property, a negative Poisson’s ratio gives a material several other beneficial effects such as an increased shear stiffness, an increased plane strain fracture toughness and an increased indentation resistance. These properties make auxetics… 

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