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The piezoelectric PZT thick films were fabricated by spinning and painting techniques in our laboratory. The purpose of this paper is to study the characteristics of the piezoelectric films that could be used as the sensors in devices, smart materials and structures. The effects of processing methods and processing conditions on dielectric properties of thick films are investigated. The temperature dependencies of the dielectric constants and the loss of the sample are measured before and after poling. Our experimental results might provide a better understanding of the behavior of these types of materials regarding their applications in monitoring, active controlling and diagnosing.

We have measured the time-dependence of the magnetization in Ba2Sr2CaCu2O single crystal under the zero field cooled condition with various magnetic fields ranging from 100 Oc to 1500 Oe along axis at different temperatures ranging from 15K to 35K. The magnetic moment decays logarithmically with time. The decay curves have been fitted with a nonlinear logarithmic function based on the Anderson-Kim thermally activated flux creep model. We have obtained the relation between the fitting parameters and the parameters provided by the Anderson-Kim model. It is believed that our experimental results agree with the predictions made by the theoretical model.

Two different processing methods were employed, hot pressing and cold pressing for fabricating Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) ceramic bulk samples, which could be used in the applications of electromechanical actuators in smart material system and structures. The dielectric constant, dielectric loss of these samples versus frequency and temperature were measured and analyzed.