Abstract: Lead zirconate titanate ceramics comprise from about 92 to 99.0 weight pent of lead zirconate and lead titanate in ratio from 0.505 to 0.54:0.495 to 0.46 respectively, from about 0.5 to about 2 weight percent of one or more fluorides or chlorides of an alkali metal or alkaline earth except francium or radium, and 0.5 to 6 weight percent of one or more oxides of magnesium, barium, chromium, scandium, aluminum, lanthanium, praesodymium, neodymium or samarium. The ceramic after pressing is annealed at a temperature from about 1050.degree. to 1350.degree. C. Ceramic elements made from the above ceramics are useful as sonar and microphone transducers.

Abstract: Strengthened and densified ceramic bodies are produced by hot pressing lead itanate powder into a lead titanate ceramic at a pressure from 1000 to 5000 psi and at a temperature from 700 to 1100.degree. C if the atmosphere is reducing or from 700 to 1200.degree. C if the atmosphere is oxidizing and by annealing the lead titanate ceramic at a temperature from 600 to 1100.degree. C in an oxidizing atmosphere for at least four hours.

Abstract: A method for strengthening lead zirconate-lead titanate ceramic transducers hich comprises heating the transducer at a temperature from 900.degree. C to 1000.degree. C in a nonreducing atmosphere containing at least 20 volume percent of oxygen for at least one hour.