Piezoelectric PMN-PT fibre hydrophone for ultrasonic transducer calibration

The University of Hong Kong, Hong Kong, 00, Hong Kong
Applied Physics A (Impact Factor: 1.69). 12/2004; 80(1):105-110. DOI: 10.1007/s00339-004-2908-3

ABSTRACT A newly developed ceramic fibre hydrophone with an active element as small as 0.25mm in diameter is described in this work. Lead magnesium niobate-lead titanate (PMN-PT) ceramic fibre with a nominal composition of 0.65Pb(Mg1/3Nb2/3)O3-0.35PbTiO3 was fabricated by an extrusion method. PMN-PT single crystals were ground to a powder form and then mixed with poly(acrylic) acid to form a homogenous slurry. The fibre was extruded by pressing the slurry through a spinneret and then sintering at 1250C for crystallization. The electrical characteristics of the PMN-PT fibre were evaluated by measuring the relative permittivity and the impedance spectrum. A piezoelectric PMN-PT fibre hydrophone was fabricated and its sensitivity, angular response, and spatial resolution were evaluated. The fibre hydrophone provides good spatial resolution, angular response and receiving sensitivity.