Dynamic effective property of piezoelectric composites with coated piezoelectric nano-fibers

摘要

This paper addresses the size-dependent dynamic effective electro-elastic properties of piezoelectric composites embedded with coated piezoelectric nano-fibers. By using the Effective Field Method of electric-elastic coupling wave, the randomly distributed coated nano-fibers in the piezoelectric media are reduced into a typical piezoelectric coated nano-fiber. To analyze the size-dependent effect, the coupling surface/interface theory is introduced to analyze the interface effect around the coating layers. Wave function expansion method is used to express the coupling wave field in the effective coupling field. The piezoelectrically stiffened elastic modulus and effective coupling wave number are obtained. Through analysis, it is found that the coupling surface/interface effect on the piezoelectrically stiffened elastic modulus show significant variation with the material properties of coating layer and the incident wave frequency. The effect of piezoelectric property of surfaces/interfaces on the effective shear modulus is also examined. Comparison with the existing results is given to validate this dynamic electro-elastic model.