Theoretical study on the static performance of piezoelectric ceramic-polymer composites with 2-2 connectivity.

The static equilibrium conditions have been derived for piezoelectric-ceramic-polymer composite structures. Rigorous solutions are obtained for a 2-2 composite of lamellar configuration. Under a uniaxial stress or an electric field the strain profile becomes inhomogeneous due to different elastic stiffness of the two components (hard piezoelectric ceramics and soft polymer). The stress transfer between the two components is identified as due to an additional shear stress produced at the ceramic-polymer interface, and the amplification factor is defined for the enhancement of the response of the active piezoelectric ceramic resulting from this stress transfer. It is shown that this enhancement effect not only depends on the volume percentage of the active component but also on the aspect ratio of the two components.