Two-Wave Shock Structures in the Ferroelectric Ceramics Barium Titanate and Lead Zirconate Titanate

Two ferroelectric ceramics, Pb (Zr0.52, Ti0.48)O3 with 1 wt % Nb2O5 and pure BaTiO3, were studied under shock wave loading. Plane shock waves having pressures ranging from 2 to 175 kbar were produced by high-explosive driving systems. Measurements were made with a streak camera and shock-detecting ferroelectric wafers. Both ceramic materials showed evidence of a two-wave structure over a wide range of shock pressures. Results indicate that these two-wave structures are characteristic of the elastic properties of the materials and are not due to phase transitions from ferroelectric to paraelectric. Pressure-volume Hugoniot curves are presented for both materials. Electrical charge released to an external load by Pb (Zr0.52, Ti0.48)O3 with 1 wt % Nb2O5 was measured as a function of the pressure of a shock which was moving parallel to the axis of polarization. The primary mechanism in this reduction of polarization by shocks was found to be, not a phase transition or domain switching, but merely a reduction of the dipole moment by axial compression.