Low-temperature sintering of (1– <i>x</i> )Pb(Zr _0.53 Ti _0.47 )O ₃ – <i>x</i> BiYO ₃ ceramics with nano-powder for piezo-speaker

Abstract

Abstract (1 −x) Pb(Zr 0.53 Ti 0.47 )O 3 − x BiYO 3 (PZT– x· BY) ceramics were synthesized by conventional bulk ceramic processing technology with various BiYO 3 (BY) doping contents. The maximum values of the piezoelectric properties were obtained in the PZT–0.01BY samples sintered at 1160 °C. After optimizing the composition of the PZT–0.01BY piezoelectrics, the sintering temperature could be lowered down to 1000 °C by applying a nano-powder technique. The maximum values of the piezoelectric properties achieved by this novel process were: d 33 of 580 pC/N, k p of 67%, and g 33 of 95 mV · m N −1 . Finally we fabricated a thick-film piezo-speaker with optimized PZT–0.01BY nano-powders using multi-layered ceramic capacitor processes. The sound pressure level (SPL) of the speaker was analyzed at a distance of 50 cm with a driving voltage of 5 V rms in the frequency range of 100 Hz–11 kHz. The measured SPL max was very high at 87 dB, which is superior quality compared with other commercial products.