Novel Piezo-active 2-1-2 Composites with Sets of Large Hydrostatic Parameters

• Published in: Ferroelectrics. Letters section Vol. 50; no. 4-6; pp. 102 - 117
• Main Author: Topolov, V. Yu
• Format: Journal Article
• Language: English
• Published: Philadelphia Taylor & Francis 02.11.2023; Taylor & Francis Ltd
• Subjects: 1-3 composite layer; 2-1-2 composite; 77.84.-s: Dielectric; and antiferroelectric materials; Elastic anisotropy; ferroelectric; Ferroelectricity; Figure of merit; Hydrostatic piezoelectric coefficients; Lithium borates; piezoelectric; Piezoelectricity; poled domain-engineered single crystal; Rods; Single crystals
• ISSN: 0731-5171; 1563-5228
• DOI: 10.1080/07315171.2023.2238175

A 2-1-2 composite with two single-crystal components is studied for the first time to highlight large hydrostatic piezoelectric coefficients d h * and g h *, figure of merit d h *g h *, and electromechanical coupling factor k h *. Each 2-1-2 composite contains layers of domain-engineered [011]-poled relaxor-ferroelectric (1-x)Pb(Zn 1/3 Nb 2/3 )O 3 - xPbTiO 3 single crystal (x = 0.0475-0.09) and heterogeneous layers being systems of aligned piezoelectric Li 2 B 4 O 7 single crystal rods in polyethylene, and these rods have an elliptic cylindrical shape. New diagrams show the volume-fraction ranges wherein large values of d h *> 10 −9 C/N, d h *g h *> 2 . 10 −10  Pa −1 and k h *≈ 0.5-0.6 are observed.