Transient Invisibility and Cloak of Impact Elastic Wave in Piezoelectric/Piezomagnetic Metamaterials

Based on the scattering cancellation technique, a piezoelectric cloaking is designed, which can make the piezomagnetic cylinder invisible to transient elastic waves. Following the Laplace transform, the piezoelectric cloaking mechanism is presented and dynamic stress concentration factor (DSCF) is derived by the plane wave expansion method. The numerical method of the inverse Laplace transformation is used to show the cloaking behavior that besides the invisible phenomenon, the DSCF is also reduced by the cloak. The piezoelectric parameter plays a positive role on enhancing the object invisibility and improving the stress distribution. These results can offer the fundamental design and application of elastic wave metamaterials.