Current developments in piezoelectric applications of ferroelectrics

Abstract The major use of ferroelectric materials continues to be in piezoelectric devices. Furthermore virtually all piezoelectric applications, with the exception of the very large business in quartz filters and oscillators, involve ferroelectric materials, mostly in ceramic form. The use of ferroelectrics in piezoelectric devices is reviewed with emphasis on the newer developments, particularly those with business potential. Features of the ferroelectric material which are desirable for the application are discussed and areas of possible improvement noted. The largest application areas have remained essentially the same for the last few years, even though there has been considerable technical improvement. They are electric wave filters, fluid loaded transducers for sonar and ultrasonic cleaning, phonograph cartridges, force transducers and high voltage ignition devices, Of these only electric wave filter devices are discussed in detail here; the others are reviewed briefly. Among newer applications whi...