Features of the piezoelectric effect in a novel PZT-type ceramic/clay composite

Piezoelectric properties, their anisotropy and sound velocity are first studied in the composite based on ferroelectric ZTS-19 ceramic of the PZT type, and the second component of the composite is piezo-passive clay. The composite as a whole is characterised by a specific porosity and elements of various connectivity patterns. The important role of microgeometric factors in the formation of piezoelectric coefficients d∗3j (j = 1 and 3) and their anisotropy ζd3j = d∗33/d∗31 is discussed in terms of connectivity patterns at the volume fraction of clay 0.01 ≤ mcl ≤ 0.35. The role of the clay component and clay-containing thin layers in the formation of the piezoelectric activity and sensitivity is interpreted within the framework of models of the two- and three-component composites based on poled ferroelectric ceramics. Results of modelling are compared to experimental data on the studied composite.