Multidimensional coupling design enables nacre-like, ultra-damping continuous piezoelectric composites

The “Brick-and-Mortar” structure endows the nacre outstanding abilities of dissipating kinetic energy, attenuating stress wave and keeping high mechanical strength. However, current artificial bio-inspired materials, such as the materials with unit structure arranged in an ordered hierarchy at merely one dimension, have yet to achieve desirable damping and mechanical behavior under monotonous damping mechanisms. Herein, the nacre-like structure, conductive network, and nano piezoelectric thin film are synergistically combined in multidimension to enhance the damping and vibration attenuating behavior by different mechanisms. The continuous piezoelectric composites with nacre-like lamellar structure demonstrates superior damping property. By introducing a conductive network, piezoelectric damping is enabled, and the damping behavior is further promoted, achieving a maximum loss factor of 1.19 and tanδ area value of 34.28. The nacre-like structure in macro dimension offers the framework of PZT thin film in nano dimension, and the conductive network in micro dimension stimulates the continuous piezoelectric damping, in which the contribution of each dimension is decoupled. Based on this finding, the vibration attenuating behavior is evaluated by cantilever beam vibration test where the composites lower 26.2 dB and damping ratio increase by 95%, which are greatly demanded for many damping applications including watercraft structures and aerospace scaffold.