A. Response of Lead Zirconate Titanate Ceramics to Temperature Fluctuations

It has been found that some shapes of lead zirconate titanate (PZT) ceramics respond to rapid temperature fluctuations when mounted in a particular geometrical configuration. This effect is presumably caused by thermal stresses in the crystal which produce a voltage difference across the silvered surfaces. These units were originally constructed to serve as pressure transducers in a lowpressure shock tube, and although a response was obtained when a shock wave (Mach number 1. 25) passed the transducer, the waveform was quite different from the waveform produced by a commercial pressure transducer. Investigation into the differences between the waveforms led to the conclusion that the transducer was sensitive to the temperature rise behind the shock wave. We report some of the results obtained with the transducer in the shock tube, describe a calibration made with a hot-air jet and a mechanical chopper wheel, and show some sample waveforms produced by spoken digits.