Anelastic loss behaviour of mobile microstructures in SrZr1-xTixO3 perovskites

Autor(en)

Zhiying Zhang, Johannes Koppensteiner, Wilfried Schranz, Michael Allan Carpenter

Abstrakt

Anelastic loss mechanisms associated with phase transitions in SrZr1-xTixO3 perovskites (x = 0.375, 0.450, 0.550, 0.775) have been investigated by dynamic mechanical analysis between 128 and 723 K at frequencies of 0.1-50 Hz. Distinctive patterns of changes in the elastic moduli due to octahedral tilting transitions correlate closely with data for the shear modulus obtained previously by resonant ultrasound spectroscopy at high frequencies (similar to 0.5 MHz). The I4/mcm Imma transition is first order and has a characteristic minimum in the shear modulus and Young's modulus. For x = 0.450 and 0.550, a dissipation peak occurs at the transition temperature, the maximum of which varies with frequency according to a power law relationship of the form tan delta = Af(n), with n approximate to -0.3. Debye-like dissipation peaks in the stability field of the Imma structure at x = 0.375 have a frequency and temperature dependence consistent with twin wall pinning by defects with an activation energy similar to 184 kJ mol(-1). These results indicate that there is diversity of pinning and relaxation processes for transformation twin walls and interfaces in different perovskites with I4/mcm, Imma and Pnma structures.

Organisation(en)

Physik Funktioneller Materialien

Externe Organisation(en)

University of Cambridge

Journal

Journal of Physics: Condensed Matter

Band

22

Anzahl der Seiten

8

ISSN

0953-8984

DOI

https://doi.org/10.1088/0953-8984/22/29/295401

Publikationsdatum

2010

Peer-reviewed

Ja

ÖFOS 2012

103018 Materialphysik

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/8c25a260-d1de-456a-91d2-f3b06ee4d698