Characterization of Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 ferroelectric crystal with enhanced phase transition temperatures

The full set of material constants for relaxor-based ternary single crystals Pb(In1/2Nb1/2)O-3-Pb(Mg1/3Nb2/3)O-3-PbTiO3 (PIN-PMN-PT) were determined and compared to binary Pb(Mg1/3Nb2/3)O-3-PbTiO3 (PMNT) crystals. The Curie temperature for rhombohedral compositions of PIN-PMN-PT was found to be in the range of 160-200 degrees C with ferroelectric rhombohedral to tetragonal phase transition on the order of 120-130 degrees C, more than 30 degrees C higher than that found for PMNT. The piezoelectric coefficients (d(33)) were in the range of 1100-1500 pC/N, with electromechanical coupling factors (k(33)) about 89%-92% comparable to PMNT crystals. The coercive field of the ternary crystal was found to be 5.5 kV/cm, double the value of the binary counterparts. The dielectric behavior under varying dc bias exhibited a similar trend as observed in PMNT with a much broader usage temperature range. Together with its enhanced field induced phase transition level, the ternary PIN-PMN-PT crystals are promising candidates for high temperature and high drive transducer applications. (c) 2008 American Institute of Physics.