Lead-free Ba0.9Ca0.1Ti0.9Zr0.1O3 piezoelectric ceramics processed below 1300 °C

Ba0.9Ca0.1Ti0.9Zr0.1O3 (BCTZ) lead-free piezoelectric ceramics were successfully prepared by Pechini polymeric precursor method using low thermal treatments. XRD analysis shows single-phase perovskite type structure for powders synthesized at 700 degrees C for 1 h. Dense ceramics were obtained from these reactive precursors using sintering temperatures below 1300 degrees C (1200 degrees C, 1250 degrees C and 1275 degrees C for 5 h). The ceramics sintered at 1275 degrees C for 5 h exhibited the best ferro-piezoelectric properties: d(33) = 390 pC/N, d(31) = -143 pC/N, k(p) = 50%, epsilon(T)(33) = 2253 and tan delta = 0.06 (100 kHz) at room temperature, T-C = 112 degrees C, 2P(r) = 24 mu C/cm(2) and 2E(C) = 4.07 kV/cm. Dense ceramics sintered at 1250 degrees C for 5 h (97% theoretical density) have average grain size approximate to 5 mu m, T-C = 115 degrees C and high ferro-piezoelectric performance (d(33) = 340 pC/N, k(p) = 49%). The high piezoelectric sensitivity is due to the high polarizability of the ceramics at local level. (C) 2013 Elsevier B. V. All rights reserved.