高強度を有する多孔質圧電セラミックスの作製と評価

Abstract

In general, the porous lead- titanate-zirconate ceramics, Pb(Zr, Ti)O3 exhibit the excellent properties for ultrasonic sensor, though the mechanical properties are not so good for their porous structure. The wide application for electronics components was restricted because of their poor reliance. In this study, the Pb(Zr, Ti)O3/SiC whisker composites (PZT/SiC) were prepared by the normal ceramics processing. With the increase in the contents of SiC whisker, the electrical and mechanical properties changed gradually. For the study of the change in properties, the microstructures were investigated by the scanning electron microscopy (SEM) and transmittion electron microscopy (TEM). The results obtained is as follows;SiC+2O2 ?? SiO2+CO2SiO2+Pb(Zr, Ti)O3 ?? Pb, Zr, Ti, Si glass.The grain boundary and three pockets were coated by this glass. As a result, the mechanical properties of bending strength and fracture toughness, K1c increased. By using this idea, the porous PZT ultrasonic sensor with a high mechanical strength has been developed and the excellent sensor properties were obtained;piezoelectric constant=99-110×10-3 Vm/Nbending strength =50 kg/cm2.