Ultrabroadband elastic cloaking in thin plates.

Area of Science:

• Materials Science
• Wave Physics
• Metamaterials

Background:

• Metamaterials are crucial for controlling wave phenomena, with recent advances in acoustic and electromagnetic cloaking.
• Controlling bending waves in thin plates is essential for various engineering applications.

Purpose of the Study:

• To propose a novel cloak design for controlling bending waves in isotropic heterogeneous thin plates.
• To demonstrate broadband performance and zero phase shift for both backward and forward scattering.

Main Methods:

• Utilized homogenization of a multilayered concentric coating with piecewise constant isotropic elastic material.
• Designed a simplified cloak structure for experimental feasibility.

Main Results:

• The proposed cloak effectively controls bending waves in thin plates.
• The cloak exhibits no phase shift for backward and forward scattering.
• A simplified 10-layer design using 6 materials demonstrated functionality over a two-octave frequency range (30 Hz to 150 Hz).

Conclusions:

• The developed metamaterial cloak offers a practical solution for wave control in thin plates.
• The design is manufacturable and has potential applications in the automotive industry and seismic protection for smart buildings.