PREDICTIONS OF STATIC DISPLACEMENTS IN 1-3 PIEZOCOMPOSITES

Piezocomposites have demonstrated higher sensitivity and lower mechani cal losses than single phase piezoelectric materials. As with any comp osite material, the properties and behavior of piezocomposites are hig hly dependent on the properties of the constituent materials and the i nterface between them. In this paper, the micromechanical behavior of 1-3 piezocomposites is investigated, An analytical model is developed for predicting the static displacement behavior of a single piezoelect ric rod embedded in a matrix. In the model, the ceramic rod is treated as transversely isotropic since it has different piezoelectric coeffi cients in the longitudinal and transverse directions. It is proposed t hat presence of a thin interlayer or polymer coating around the cerami c rods can influence the longitudinal displacement of the rods and cha nge the overall sensitivity. A composite cylinder model is adopted to incorporate the presence of an interlayer with varying properties. The oretical predictions indicate that the introduction of a compliant int erlayer greatly increases the out-of-plane displacement of the rod and the sensitivity of the composite.