Rayleigh wave propagation in a homogeneous centrosymmetric flexoelectric half-space.

Although Rayleigh waves are a research topic of constant interest, research on Rayleigh waves in flexoelectric materials is still lacking. This study reports the influences of flexoelectricity, strain gradient elasticity, micro-inertia effect and surface effect on Rayleigh waves in a homogeneous centrosymmetric flexoelectric material half-space. The nonclassical governing equations and boundary conditions are deduced with Hamilton's principle. Our findings suggest that the influence of flexoelectricity on the phase velocity depends on the flexoelectric coefficients. Strain gradient elasticity and surface elasticity can increase the phase velocity, while micro-inertia effect can decrease the phase velocity. Besides, these influences become significant for Rayleigh waves with high frequencies and short wavelengths. A mathematical foundation may be established to measure the material properties on the basis of the relationships among the material parameters, the phase velocity and the wave number. Moreover, the current work might provide guidance in developing small-scale acoustic wave devices operating at high frequencies.