Effects of uniaxial stress on dielectric properties of ceramics in PMN-PZT system

In this study, effects of uniaxial stress on the dielectric properties of ceramics in PMN-PZT system were investigated. The ceramics with a formula (1-x)Pb(Mg1/3Nb2/3)O3-(x)Pb(Zr0.52Ti0.48)O3 or (1-x)PMN-(x) PZT when x = 0.0 0.3 0.5 0.7 and 1.0 were prepared by a conventional mixed-oxide method. Phase formation behavior of these ceramics was studied by an X-ray diffraction (XRD) method. In addition, other physical properties, e.g. firing shrinkage and density, were measured. The dielectric properties under the uniaxial stress of the poled PMN-PZT ceramics were observed at low and high-stress levels using a uniaxial compressometer. It was found that at low stress level (0-800 kPa) there was no significant change in the dielectric constant and the dielectric loss tangent with the applied stress. As the stress level was raised higher (0-5 MPa), changes of the dielectric constant with the applied stress were dependent on the ceramic compositions. On the other hand, changes of the dielectric loss tangent with the applied stress were independent of the ceramic compositions.