5. Prediction of Effective Properties of Composites Based on Ferroelectric Ceramics

The important step at the study of the piezo-particulate composites is concerned with the prediction of their effective properties. Hereby a number of models have been put forward at modelling and interpretation of the properties. Examples of the effective piezoelectric properties and related parameters of 0–3, 1–3 and 2–2 ferroelectric ceramic/polymer composites, and 0–3-type composites with two kinds of the ceramic inclusions are discussed to demonstrate the influence of microgeometric characteristics, components and other factors on the electromechanical coupling and piezoelectric performance of the composites. The effective pyroelectric and dielectric properties of the ceramic-based composites are considered to a lesser degree. The microgeometry of the piezo-active composite plays a key role in determining its piezoelectric sensitivity, and changes in the microgeometry can lead to appreciable changes in the piezoelectric sensitivity and related parameters. Main examples of the piezoelectric sensitivity are concerned with composites that are based on either the PZT-type or PbTiO₃-type ceramics. Calculated parameters are compared to the known experimental data.