The complex structural mechanisms behind strain curves in bismuth sodium titanate–barium titanate

摘要: In this work, the lead-free composition (1-x)Bi0.5Na0.5TiO3–xBaTiO3 (BNT–BT) with x = 0.12 was investigated using in situ Synchrotron x-ray powder diffraction. With applied electric field, pseudo-cubic relaxor phase reversibly transforms to a ferroelectric state. The reversibility is still preserved after 104 bipolar field cycles. A Rietveld refinement structure, strain, and texture analysis model based on atomic scale for four frequencies from 10−4 101 Hz. allowed us separately determine two coexisting phases, their dependent evolution, underlying strain mechanisms. For all frequencies, we showed that domain switching only mechanism appearing tetragonal lattice rhombohedral phase. coercive of (4 kV/mm) found be higher than (3 kV/mm). This divergence has not been observed previously lead-containing materials cannot detected solely macroscopic polarization experiments. Moreover, abruptly starts occur threshold value exhibits high hysteresis. other hand, nearly beginning increases more linearly during cycle. It could, therefore, demonstrated complex structural mechanisms underlie apparent clear continuous curve. These findings are crucial actuator undergoing transformation provide approaches strategies optimize tailored applications.