4. Stress Concentration, Fracture and Damage in Auxetic Materials

This chapter considers the damage properties of auxetic solids. In the study of stress concentration factors in auxetic solids and plates arising from cavities and rigid inclusions, most cases exhibit minimum stress concentration when the solids possess negative Poisson’s ratio. In discussing the three modes of fracture in auxetic solids in dimensionless terms, most plots exhibit a clear demarcation between auxetic and conventional regions. The consideration of damage criteria based on thermodynamic analysis by Lemaitre and Baptiste (NSF workshop on mechanics of damage and fracture, 1982) shows that as an isotropic solid changes from conventional to auxetic, the damage criterion shifts from being highly dependent on the von Mises equivalent stress to being highly dependent on the hydrostatic stress. Progress on fatigue failure of auxetic materials is then given.