Flexural wave propagation in double-layered nanoplates with small scale effects

In this work, the flexural wave propagation in doubled-layered nanoplates is studied. Based on the nonlocal continuum theory, the equation of wave motion is derived. The frequency, phase velocity, group velocity, and their ratio with different scale coefficients and wave numbers are presented. From the results, it can be observed that the small scale effects should be considered for higher frequencies. The dispersion properties for mode I and mode II are different. The van der Walls (vdW) interaction has significant influence on the wave characteristics for the higher mode, which is similar to the vibration properties of nanoplates. However, not all of the characteristics for mode II can be dominated by the vdW interaction, they can be affected by the wave number and the scale coefficients.