Electromechanical characterization of Pb(In0.5Nb0.5)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3 crystals as a function of crystallographic orientation and temperature

Relaxor based Pb(In0.5Nb0.5)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3 ternary single crystals (PIN-PMN-PT) were reported to have broader temperature usage range (TR-T) and comparable piezoelectric properties to Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMNT) crystals. In this work, the orientation dependent dielectric, piezoelectric and electromechanical properties for PIN-PMN-PT crystals were investigated along ⟨001⟩ and ⟨110⟩ directions. The electromechanical couplings k33 and k32 for ⟨110⟩ poled crystals were found to be 0.91 and 0.91, respectively, with piezoelectric coefficients d33 and d32 on the order of 925 and −1420 pC/N. Of particular significance was the mechanical quality factor Q33 for ⟨110⟩ oriented crystals, which was found to be ≥500, much higher than the Q values of ⟨001⟩ oriented relaxor-PT crystals (Q∼70–200). The temperature dependence of the piezoelectric properties exhibited good temperature stability up to their ferroelectric phase transition TR-T∼125 °C, indicating ⟨001⟩ and ⟨110⟩ oriented PIN-PMN-PT are promising materials for transducer applications, with the latter for high power resonant devices where low loss (high Q) was required.