Correlation between enhanced lattice distortion and volume fraction of polar nanoregions in quenched Na_1/2Bi_1/2TiO₃–BaTiO₃ ceramics

Quenching has been established as a viable method to increase the depolarization temperature in (100-x) Na1/2Bi1/2TiO3–xBaTiO3 (NBT–xBT). The proposed hypothesis of stabilized ferroelectric order would entail changes polarized volume. To this end, air-quenched and furnace cooled samples four compositions NBT–xBT with x = 3, 6, 9, 12 mol. % BT were studied. Upon quenching, all demonstrate an relaxor transition temperature, TF-R, by 23–44 °C enhanced lattice distortion. Resonance frequency damping analysis was utilized measure Young's modulus range 25 800 estimate volume fraction polar nanoregions using composite model. leads 8% decrease modulus, but 12% at 300 for NBT-6BT. Transmission electron microscopy investigations quenched NBT-6BT reveal combination lamellar domains more homogenous areas nanometer-sized domains. existence morphotropic phase boundary together distortion dielectric dispersion substantiate premise order.