SINTERABILITY AND PIEZOELECTRIC PROPERTIES OF KNbO3 CERAMICS AFTER SUBSTITUTING Pb AND Na FOR K

KNbO3 ceramics are usually porous due to their poor sinterabilty under ordinary firing in air, although the single crystal exhibits a large amount of piezoelectricity. Authors found a marked improvement in the sinterability of KNbO3 ceramics on substituting a small amount of Pb for K. However, the amount of piezoelectricity of the ceramics was small due to their fine grains ( < 0.2 mu m). In order to realize large grains, authors substituted Na and Pb for K, and fired the ceramics for long periods of time. 12 refs.