Fabrication and properties of 1-3 PZT-polymer composites

Abstract

Cost effective manufacturing processes have been demonstrated for 1-3 PZT-polymer composite transducers which can be scaled to large areas. PZT ceramic preforms containing uniform rods aligned in a precise array are produced by injection molding. The PZT preforms contain 361 rods which are 1.1 mm diameter and 8 mm long. The preforms are sintered, poled, laid up to make composites of arbitrarily large size, and then encapsulated into a polymer matrix. Composites have been produced with both flexible and rigid polymers. The composites are machined flat and parallel and then electroded. Several 100 mm square transducers with a composite thickness of 6.3 mm have been fabricated and evaluated. These have shown good performance both as projectors and hydrophones. Transducer fabrication has been scaled to 250 mm square panels. Ultrafine scale 1-3 PZT composites have also been produced by injection molding. Uniform arrays of 120 {mu}m diameter, 1000 {mu}m long PZT fibers in an epoxy matrix have been produced. PZT 1-3 composite arrays with fibers as small as 70 {mu}m diameter and an aspect ratio of 10 have also been fabricated.