Appearance of Supersonic Stoneley Waves in Auxetics

Abstract

It is shown that in auxetic materials (materials with negative Poisson’s ratio), supersonic Stoneley waves travelling without attenuation with a velocity equal to or exceeding maximum bulk wave velocity, may exist. Analytical expressions for the relation between negative Poisson’s ratio and Young’s moduli of the contacting isotropic media ensuring the condition of propagation for supersonic Stoneley waves, are derived by solving a secular equation for Stoneley waves.

Keywords

• auxetic
• Stoneley wave
• isotropy
• velocity
• secular equation
• inhomogeneity