Effect of transformation twins on the anelastic behavior of polycrystalline Ca1-xSrxTiO3 and SrxBa1-xSnO3 perovskite in relation to the seismic properties of Earth's mantle perovskite
The mechanical loss of Ca1-xSrxTiO3 as a function of temperature has been studied up to 1000 deg C using dynamical mechanical analysis. The loss spectrum reveals a relaxation peak in the tetragonal phase and negligible mechanical loss in the cubic and orthorhombic phases. The peak is accompanied by...
Saved in:
Published in | Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 442; no. 1-2; pp. 199 - 203 |
---|---|
Main Authors | , , , |
Format | Conference Proceeding Journal Article |
Language | English |
Published |
Amsterdam
Elsevier
20.12.2006
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | The mechanical loss of Ca1-xSrxTiO3 as a function of temperature has been studied up to 1000 deg C using dynamical mechanical analysis. The loss spectrum reveals a relaxation peak in the tetragonal phase and negligible mechanical loss in the cubic and orthorhombic phases. The peak is accompanied by a softening of the storage modulus, caused by the formation of mobile transformation twin domain walls. The small value of internal friction in the orthorhombic phase is associated with a negative volume strain, resulting in domain walls that are strongly pinned by lattice defects. The volume changes and mechanical loss in Ca1-xSrxTiO3 are compared with those in SrxBa1-xSnO3, a system which shows a positive volume strain. In contrast to Ca1-xSrxTiO3, SrxBa1-xSnO3 displays a thermally activated peak in the orthorhombic phase. A frequency-independent peak attributed to the tetragonal-orthorhombic transition is also seen. The positive volume strain in SrxBa1-xSnO3 results in domain wall structures that are less strongly pinned by lattice defects. |
---|---|
Bibliography: | SourceType-Scholarly Journals-2 ObjectType-Feature-2 ObjectType-Conference Paper-1 content type line 23 SourceType-Conference Papers & Proceedings-1 ObjectType-Article-3 |
ISSN: | 0921-5093 1873-4936 |
DOI: | 10.1016/j.msea.2006.01.141 |