Properties of fine scale piezoelectric PZT fibers with different Zr content

Smart materials containing piezoelectric fibers have a large potential in sensoric, actuatoric and ultrasonic transducer applications. Fine scale PZT fibers with five systematically adjusted Zr/Ti ratios ranging from x = 58/42 to 48/52 have been prepared using a sol-gel route. The fibers were embedded in a polymer matrix to produce 1-3 composites and the effective piezoelectric and dielectric coefficients were measured. An analytical model was used to extract the corresponding values of the fibers from the effective material properties. The dependence of the coefficients on the Zr/Ti ratio shows a pronounced maximum at x = 53/47. This correlates with an analysis of the phase content. For x = 53/47 the fibers consist of 31 % rhombohedral and 69 % tetragonal phase, whereas the content of rhombohedral phase is 100 and 7 % for x = 58/42 and 48/52, respectively. For x = 53/47 maximum values of epsilon (T)(33) = 1200 and d(33) = 127 pm/V were found. The latter one is about 50 % of the value of corresponding bulk materials. (C) 2001 Elsevier Science Ltd. All rights reserved.