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This paper reports results on effective piezoelectric properties of advanced composites based on polydomain relaxor-ferroelectric single crystals of 0.67Pb(Mg1/3Nb2/3)O3 - 0.33PbTiO3. Two variants of the single crystal/porous polymer composite with 0-3-0 connectivity are proposed to study the role of microstructural factors in forming high piezoelectric sensitivity. The effective properties of the related 0-3 single crystal/polymer composite are predicted and considered to show ways of increasing the piezoelectric anisotropy and sensitivity. Examples of the volume-fraction and aspect-ratio dependences of the effective piezoelectric coefficients d3j*, g3j*, the hydrostatic piezoelectric coefficient gh*, and squared figures of merit d33* g33* and dh* gh* of composites are analysed to show in which ranges high piezoelectric sensitivity is attained. The presence of single-crystal polydomain inclusions in the porous 3-0 matrix promotes the large effective parameters (g33* ∼ 103 mV · m/N, gh* ∼ 103 mV · m/N, d33* g33* ∼ 10-10 Pa-1, and dh* gh* ∼ 10-10 Pa-1), and the obvious high-performance advantage of the 0-3-0 composites is discussed taking into account features of their microstructure. [ABSTRACT FROM AUTHOR]

Abstract: The 2–2–0 single-domain 0.67Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 crystal/porous polyurethane composite is studied in which the orientation of the spontaneous polarisation vector Ps of crystal, its volume fraction and the volume fraction and shape of pores in polymer are varied to attain maxima (minima) of effective hydrostatic piezoelectric coefficients and , squared figure of merit and electromechanical coupling factor . This paper describes an effect of the Ps orientation and the shape of pores on the hydrostatic piezoelectric response of this composite. Advantages caused by large values of , , , and of the studied composite are discussed. [Copyright &y& Elsevier]