Shock wave compression of the ferroelectric ceramic Pb0.99(Zr0.95Ti0.05)0.98Nb0.02O3: Depoling currents

Abstract

Shock wave compression of poled Pb0.99(Zr0.95Ti0.05)0.98Nb0.02O3 (PZT 95/5-2Nb) results in rapid depoling and release of bound charge. In the current study, planar-impact experiments with this material were conducted on a gas-gun facility to determine Hugoniot states, to examine constitutive mechanical properties during shock propagation, and to investigate shock-induced depoling characteristics. A previous article summarized results from the first two of these areas, and this article summarizes the depoling studies. A baseline material, similar to materials used in previous studies, was examined in detail. More limited experiments were conducted with other materials to investigate the effects of different porous microstructures. Experiments were conducted over a wide range of conditions in order to examine the effects of varying shock strength, poling orientation, input wave shape, electric field strength, porous microstructure at a fixed density, and initial density. Depoling currents were recorded in an external circuit under either short-circuit or high-field conditions, and provide a convenient means of examining the kinetics associated with the ferroelectric–to–antiferroelectric phase transition. For sufficiently strong shock waves, the measured short-circuit currents indicate that the phase transition is very rapid and essentially complete. As shock strengths are reduced, short-circuit currents show increasing rise times and decreasing final levels at the end of shock transit. These features indicate that the transition kinetics can be characterized in terms of both a transition rate and a limiting degree of transition achieved in a given shock experiment. The presence of a strong electric field does not appear to have a significant effect on transition kinetics at high shock stresses, but has a strong effect at low stresses. As was found for constitutive mechanical properties, only small effects on measured currents resulted from differences in the porous microstructure of common-density materials, but large effects were observed when initial density was varied. To examine transition kinetics in more detail, short-circuit currents obtained with the baseline material and several approximate methods were used to estimate values for the rate and degree of transition as functions of shock properties. Differences between these currents and currents measured in high-field experiments using the same impact conditions were used to examine field effects on transition kinetics and corresponding dielectric properties.

Ultrahigh energy density harvested from domain-engineered relaxor ferroelectric single crystals under high strain rate loading

“…These PZT 52/48 and 95/5 results are in good agreement with previous results of transverse depolarization of the two ferroelectrics1721.…”

The Charge Release and Its Mechanism for Pb(In1/2Nb1/2)–Pb(Mg1/3Nb2/3)–PbTiO3 Ferroelectric Crystals Under One‐Dimensional Shock Wave Compression

“…First, the initial currents for PZT95/5 ceramic and PIN‐PMN‐PT crystals are opposite in direction. At 3.0 GPa pressure, the polarization vector of PZT95/5 ceramic changes from initial value to zero with the occurrence of FE‐AFE phase transitionThe current direction of PIN‐PMN‐PT crystals keeps opposite to that of PZT95/5, it is confirmed that the polarization of PIN‐PMN‐PT is increased under shock wave compression. Second, different from PZT95/5, PIN‐PMN‐PT crystal has reversed current after negative current.…”

“…Since Neilson reported the rapid depolarization of ferroelectric ceramics induced by shock waves compression in 1957, numerous investigations on the ferroelectric materials under shock wave compression have been reported. Due to the application of explosively driven pulsed power supply, the research in this field mainly focused on the ferroelectric–antiferroelectric (FE‐AFE) phase transition induced by shock compression . The ferroelectric ceramics with composition close to the FE/AFE phase boundary, such as (PbZr 0.95 Ti 0.05 O 3 ) PZT95/5, present a small free energy difference between FE and AFE phases, and the FE‐AFE phase transition could be easily induced by pressure.…”

Electrical response of Pb(Zr0.95Ti0.05)O3 under shock compressions

“…The same phenomenon was also observed in porous PZT 95/ 5 at 2.4 GPa, which was due to dynamic yielding, but porous PZT 95/5 behaves normally at 3.0 GPa. 10 Thus, mechanical failure at low stresses did not immediately cause electrical breakdown, even when cracks were already present in the PZT 95/5. This only occurred when the stress was increased to 4.3 GPa and the samples were full of the cracks, in which case 100% electrical breakdown was observed and the breakdown strength decreased.…”

“…For PZT 95/5, the empirical equation for P fsc is 10 ðP r À P f sc Þ=P r ¼ 1:26 À 0:59r À1 s ; 0:5 < r s < 2:5; (2) where r s is the shock stress in GPa. According to Kirchhoff's current and voltage laws, the relationships below were obtained…”