Predicting the Adaptation of Biomimetic Auxetic Materials to Mechanical Impact

To descript biomimetic material behavior under localized damage, two novel parameters which characterizing the damage-induced volume change coefficient and the stress concentration coefficient were introduced. A computational methodology was developed to determine these parameters for both isotropic materials and in-plane cross-ply composites. The effect of Poisson’s ratio ν of the materials under consideration on the change in the volume of localized damage and stress concentration under various deformation conditions was investigated. At uniaxial stress state the relative reduction in damage volume under compression of an isotropic auxetic material with ν < 0 is significantly (twofold or more) greater than that of a material having ν > 0. For the cross-ply composite, a range of reinforcement angle variation was identified that is preferable based on the criteria of damage volume and stress concentration parameters.