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The solid solution of (x)Ba0.7Ca0.3TiO3-(1-x)BaZr0.2Ti0.8O3 is known to exhibit high piezoelectric constants. Discrepancies in the reported phase transitions and structure around room temperature, however, have complicated the understanding of the enhanced ...
Elastic storage modulus and loss of relaxor lead magnesium niobate ceramics, Pb(Mg1/3Nb2/3)O3, have been measured with dynamic mechanical analyzer in single cantilever mode in the temperature range from 170K to 320K and at frequencies from 0.1 Hz to 50 Hz. ...
Dense and phase-pure ferroelectric ceramics of 75 mol.% Bi0.5K0.5TiO3 - 25 mol.% BiFeO3 are prepared by the conventional solid state reaction method. Their crystal structure is analyzed and discussed. The dielectric and piezoelectric properties of the cera ...
A uniaxial compressive stress significantly modifies the dielectric and piezoelectric response of Pb(Zr,Ti)O3 (PZT)-based piezoceramics. In soft PZT, the pre-stress decreases both the piezoelectric coefficient and its increment with increasing dynamical st ...
We report on the frequency and stress dependence of the direct piezoelectric d33 coefficient in BiFeO3 ceramics. The measurements reveal considerable piezoelectric nonlinearity, i.e., dependence of d33 on the amplitude of the dynamic stress. The nonlinear ...
The dielectric response in Bi4Ti3O12 single crystals was studied at subswitching conditions at relative low temperatures (20-250 degrees C) and frequencies (100 mHz to 10kHz) both in-plane and out-of-plane. Electron-holes are likely to be the major charge ...
Sodium bismuth titanate (NBT) ceramics are among the most promising lead-free materials for piezoelectric applications. This work reports the crystal structure and phase evolution of NBT and Fe-modified NBT (from 0-2 at.% Fe) using synchrotron x-ray diffra ...
In this work, the effect of introducing tetragonal yttria-stabilized zirconia (TZ) particles in soft [Pb0.98Ba0.01][(Zr0.53Ti0.47)(0.98)Nb-0.02]O-3 (PZT) was investigated. Both microstructure and electrical properties of the PZT-xTZ (x = 0, 2, 5, 10, 20 vo ...
This work was originally motivated by the search for high-temperature piezoceramic materials with low acoustic impedance and high electromechanical coupling. The temperature and pressure behavior of two PZT-based materials with engineered porosity, Pz31 & ...
The solid solution 0.5Ba(Ti0.8Zr0.2)O-3-0.5(Ba0.7Ca0.3)TiO3 (BCZT) is a promising lead-free piezoelectric material with exceptionally high piezoelectric coefficients. The strong response is related to structural instabilities close to ambient temperature. ...