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The pulsed power supply that generates megawatts of electrical power has drawn important attention for many decades. Despite that the large energy output has been obtained in lead-containing materials such as Pb(Zr0.95Ti0.05)O3 (PZT95/5) ceramics, lead-free ferroelectric candidates are highly desired due to the environmental concerns. In this work, we report the depolarization behavior of lead-free ternary 0.99[0.98(Bi0.5Na0.5)(Ti0.995Mn0.005)O3-0.02BiAlO3]-0.01NaNbO3 ferroelectric ceramics under shock wave compression. A current profile with a maximum value of ∼25 A and a FWHM of ∼2.3 μs was obtained. Particularly, the poled BNT-BA-0.01NN ceramics were almost completely depolarized under high strain rate loading, releasing a high charge density J of 38 μC/cm2. The released J was approximately 96% of thermal-induced charge density (∼40 μC/cm2), which was 18% higher than that of PZT95/5 ceramics. The shock-induced depolarization mechanism can be attributed to the ferroelectric-ergodic relaxor phase transition. These results reveal the BNT-based ceramics as promising candidates for pulsed power applications. [ABSTRACT FROM AUTHOR]

Several 0.97PbZrO3–0.03Ba(Mg1/3Nb2/3)O3 (0.97PZ–0.03BMN) ceramics were prepared via the columbite precursor method. Their microstructures and pressure-dependent ferroelectric and depolarization performances were then studied. The X-ray diffraction patterns of ground and fresh samples indicate that a main rhombohedral symmetry crystal structure is present in the bulk and that it sits alongside a trace quantity of an orthorhombic antiferroelectric phase that results from the effect of grinding on the surface. The remanent polarization (Pr) of the 0.97PZ–0.03BMN reached 32.4 μC/cm2 at 4.5 kV/mm and ambient pressure. In an in situ pressure-induced current measurement, more than 91% of the retained Pr of the pre-poled sample was released when the pressure was increased from 194 MPa to 238 MPa. That this pressure-driven depolarization should be attributed to the pressure-induced ferroelectric–antiferroelectric phase transition is supported by the emergence of double P–E loops at high hydrostatic pressures. Moreover, the 0.97PZ-0.03BMN ceramics exhibit no temperature-induced phase transitions and little related polarization loss up to 125 °C, which suggests that Pr has excellent thermal stability. The sharp depolarization behavior at low pressures and excellent temperature stability reveal that our 0.97PZ–0.03BMN ceramics exhibit superior performances in mechanical–electrical energy conversion applications. [ABSTRACT FROM AUTHOR]