New piezoceramic PZT–PNN material for medical diagnostics applications

The development of a new piezoceramic material, Ferroperm Pz21, optimised for use in medical diagnostics applications is described. The requirements to such a material are very high permittivity, sensitivity and coupling factors, and at the same time a relatively high Curie temperature. The structure must furthermore be very dense and fine-grained, since dicing of small sub-elements for medical arrays must be performed without damaging the material. The developed material is a solid solution between a PZT phase and the relaxor phase Pb(Ni1/3Nb2/3)O3. A comparison between different production processes is given, and a new solid state route for production of very dense and fine-grained materials is presented. Very positive characteristics are generally observed, and a stable behaviour even at elevated temperatures indicate that the material can find applications not only in the medical market, but also as a more general sensor/actuator.