NON-180-DEGREES DOMAIN CONTRIBUTION IN ELECTRIC-FIELD-INDUCED STRAINSOF PZT CERAMICS MEASURED BY A MACH-ZEHNDER INTERFEROMETER

In order to evaluate the contribution of the non-180 degrees domain re orientation in the electric-field-induced strains of PZT ceramics, a M ach-Zehnder interferometer was constructed and the electric-field-stra in of PZT ceramics was measured as a function of frequency. The perfor mance of the interferometer was confirmed using a LiNbO3 single crysta l and PZT ceramics. The piezoelectric constant of PZT ceramics determi ned by the interferometer well agreed with that determined by the reso nance method and the result of LiNbO3 single crystal was also approxim ately consistent with the literature. The resolution of the interferom eter was about 0.01 nn. The electric-field-induced strain curve showed a hysteresis under high electric fields and low frequencies. The appa rent piezoelectric constant determined from the electric-field-induced strain increased with decreasing frequency under high electric fields . These behaviors were interpreted as the effect of non-180 degrees do main reorientation.