Comparison of internal friction and torsion strain spectra for the cubic–tetragonal transformation of PMN‐32PT crystal

Abstract

Internal friction and torsion strain spectra are compared for PMN-32PT crystal and it is found that the abrupt changes and random bouncing of the torsion strain are ascribed to a cubictetragonal transformation, which is accompanied by a large internal friction peak. This observation confirms that the cubictetragonal transformation of PMN-32PT crystal is a burst-type martensite transformation. We propose that it is caused by a parallel order-disorder transformation taken by the polar nanoregions (PNRs) inside PMN-32PT, during which 908-domain twins inside the PNRs perform reorientations to satisfy the constraint of macroferroelectric domains.