Elastic anomalies associated with transformation sequences in perovskites: II. The strontium zirconate–titanate Sr(Zr,Ti)O₃solid solution series

Abstract

The sequence of phase transitions due to octahedral tilting across the Sr(Zr,Ti)O 3 solid solution series has been investigated by resonant ultrasound spectroscopy at high and low temperatures using ceramic samples. The elastic behaviour associated with phase transitions as a function of composition in Sr(Zr,Ti)O 3 at room temperature is proposed to be analogous to that as a function of temperature in what is assumed to be I mma, appear to have stability fields across the full compositional range and both show large dissipation effects, most probably due to twin wall mobility. In contrast, the Zr-rich Pnma phase, which should contain transformation twin walls, is an unexpectedly stiff and non-dissipating material, similar to the high temperature and/or Ti-rich Pm3m phase. In the case of Pnma, this is attributed to coupling between the two order parameters, which could impede relaxation responses to an applied stress. The Pm3m structure is a classically stiff cubic perovskite and no transformation-related dissipation processes are expected.

Local Symmetry Breaking in the Bulk and in Domain Boundaries: Breit–Wigner Damping of Phonons and Acoustic Resonances

“…Above the cubic-tetragonal transition temperature (106 K), all the resonance peaks were sharp and close to being symmetrical with Lorentzian profiles. As has been reported elsewhere [35,36], the transition is marked by a steep increase in acoustic dissipation such that the resonance peaks are not usually detectable in the stability field of the tetragonal structure. This was attributed to anelastic motion of twin walls.…”

Structural, microwave dielectric properties and dielectric resonator antenna studies of Sr(ZrxTi1−x)O3 ceramics

“…Sr(Zr x Ti 1−x )O 3 is formed by the substitution of Ti 4+ ions (atomic weight of 47.9 g/mol, ionic radius of 74.5 pm) by Zr 4+ ions (atomic weight of 91.2 g/mol, atomic radius of 86 pm) at B-site of ABO 3 perovskite [25,26]. Many fundamental research including elastic behavior and structural analysis of Sr(Zr,Ti)O 3 ceramics have been already studied [27]. An even ultra wide range dielectric spectrum from kHz to THz has already been discussed using IR-reflective method [28].…”

Microstructure dynamics in orthorhombic perovskites

“…All three are improper ferroelastics containing transformation twins but the twin walls appear to be mobile only in the rhombohedral and tetragonal phases of LaAlO 3 , ͑Ca, Sr͒TiO 3 , and Sr͑Zr, Ti͒O 3 . [8][9][10][11][12][13][14][15][16] In Ca 1−x Sr x TiO 3 with x = 0.4, 0.45, and 0.5, and in SrZrO 3 , transitions to the Pnma structure are marked by a steep decrease in anelastic softening and dissipation as if twin wall motion is abruptly curtailed. 9,14,15 Two different explanations have been offered.…”