Rate independence of material properties and remnant state variables during domain switching by electric field or stress in ferroelectric ceramics at room and high temperatures

Various numbers of electric field or compressive stress pulses with increasing magnitude are applied to a poled lead titanate zirconate rectangular parallelepiped specimen. Changes in linear material properties are estimated from measured responses and plotted versus remnant polarization. The dependence of linear material properties on remnant polarization is shown to be the same independent of the overall rate of domain switching by electric field or stress at room and high temperatures. The evolution path of remnant polarization and strains in the plane of remnant state variables is also found to be equal independent of switching rate at room and high temperatures. Finally, when the values of remnant state variables at high temperature are transformed to those of reference remnant state variables, the evolution path of the reference remnant state variables is compared to be coincident with that of remnant state variables at room temperature, implying the same switching process at different temperatures.