Piezoelectric Ceramics

The discovery of piezoelectric effects in electrically poled barium titanate ceramic, in the early l940, was a revolutionary contribution to the electromechanical transducer art. Since then, improved barium titanate ceramics adapted to a variety of practical needs have been developed, and a number of new piezoelectric oxide‐type compounds have been discovered. Among these the lead titanate zirconate group offers especially valuable properties. In addition to a survey of the field, the present paper presents new data on lead titanate zirconate over a range of compositions.