Phase-dependence of dielectric constants on ferroelastic domain switching stress for Pb3(PO4)2

The dependence of the dielectric constants on the applied sinusoidal mechanical field for Pb-3(PO4)(2) was investigated near the transition temperature, 180 degrees C. In the ferroelastic phase, the dielectric constant showed periodic change depending on the applied stress, which is caused only by the ferroelastic domain switching. The increase and decrease of the dielectric constants under the tensional and compressive stress are attributed to the orientation change of domain under the stress. At the maximum and the minimum stress, the dielectric constants show no more sharp increase and decrease, because near these stresses possible domains were already switched to another orientation state. The dielectric change of the ferroelastic compounds under the sinusoidal stress is defined as a ferroelastic piezo-displacement.