Creep behavior of a poled PZT wafer under longitudinal tensile stress and through thickness electric field

A commercially available soft PZT wafer that is poled in thickness direction is subjected to three different sets of loading environment, and variations of electric displacement in thickness direction and longitudinal/transverse strains are measured over time. Pure tensile stress creep experiments are made in short and open-circuit conditions. Different material responses in the two electrical boundary conditions are explained by the effects of piezoelectrically produced internal electric field on linear material moduli and domain switching mechanisms. The material responses under pure antiparallel electric field load and combined load are compared with each other and the differences are explained by the opposite effects of longitudinal tensile stress on 90° domain switching.