Abstract
The crystallization evolution of lead zirconate titanate (PZT) powders processed from two organic gel systems with nominal composition was investigated. The crystallization of the perovskite PZT form initiated as the calcining temperature reached 400 degrees C. The formation of PbO phase constituted seeding grains for PZT crystallization at such low temperature. The formation of lead-deficient fluorite or pyrochlore phases was completely avoided under judicious processing conditions. TGA/DTA analysis was carried out to evaluate the activation energy associated with the perovskite phase formation. The kinetic parameters of the PZT crystallization toward perovskite formation were followed by employing Kissinger and JMAK isoconversional kinetic models. The results revealed that the crystallization mechanism is related to the powder precursor system. The value of the activation energy for the perovskite formation was about 77 kJ mol(-1) irrespective of the precursor system when the Kissinger model was applied.