Orientation dependence of dielectric and piezoelectric properties of (K0.95Li0.05) (Ta0.40Nb0.60) O3 single crystal

(K0.95Li0.05) (Ta0.40Nb0.60) O-3 (abbreviated as 0.60: KLTN) single crystal has been grown by the top-seeded melt growth method. Dielectric properties in the a- and c-direction have been investigated, and the high anisotropy has been found. epsilon(11)=2130, while epsilon(33)=371 were determined in the unpoled sample. The piezoelectric constants and electromechanical coupling factors have been determined which are d(15)= 190 pC/N, d(31) = -140 pC/N, d(33)=400 pC/N, k(15)=49.4%, k(31)=56.2% and k(33)=75.0%. The crystal orientation dependences of dielectric, piezoelectric and electromechanical coupling properties have been simulated by using the mathematical approach along with phenomenology of the system. These results will be of use for developing high performance lead-free piezoelectric devices. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.