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Title: High-temperature deformation behavior in Sr TiO{sub 3} ceramics.

Abstract

The high-temperature deformation behavior of a polycrystalline strontium titanate (SrTiO{sub 3}) ceramic (6 {micro}m grain size) was investigated at temperatures of 1200-1345 C in an argon atmosphere. Compressive deformation tests were conducted at strain rates ranging from 5 x 10{sup -6} to 5 x 10{sup -5} s{sup -1}. Steady-state flow stresses were 0.05-30 MPa and increased with increasing strain rates. Stress exponents of {approx}1, at temperatures >1200 C, indicated a viscous diffusion-controlled deformation with an activation energy of {approx}628 {+-} 24 kJ/mol. Comparison of activation energy with literature data suggests diffusion of cations as the rate-controlling mechanism. Absence of cavitation and grain-shape changes were consistent with grain-boundary sliding as the principal deformation mechanism. The electron back-scattered diffraction (EBSD) technique was used to determine the grain orientation as a function of applied strain. The results indicate that some of the grains rotate with cumulative rotation as large as 7 degrees at a strain of 4%.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
EE
OSTI Identifier:
914805
Report Number(s):
ANL/NE/CP-118953
TRN: US200812%%75
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Conference
Resource Relation:
Journal Name: J. European Ceram. Soc.; Journal Volume: 27; Journal Issue: 11 ; 2007; Conference: Mechanical Properties in Advanced Materials: Recent Insights; Jun 7-11, 2006; Fuenteheridos, Spain
Country of Publication:
United States
Language:
ENGLISH
Subject:
36 MATERIALS SCIENCE; ACTIVATION ENERGY; CERAMICS; DEFORMATION; GRAIN ORIENTATION; GRAIN SIZE; MECHANICAL PROPERTIES; STRAIN RATE; STRONTIUM TITANATES

Citation Formats

Singh, D., Lorenzo-Martin, M., Chen, G., Gutierrez-Mora, F., Routbort, J. L., Nuclear Engineering Division, and Univ. de Sevilla. High-temperature deformation behavior in Sr TiO{sub 3} ceramics.. United States: N. p., 2007. Web. doi:10.1016/j.jeurceramsoc.2007.02.186.
Singh, D., Lorenzo-Martin, M., Chen, G., Gutierrez-Mora, F., Routbort, J. L., Nuclear Engineering Division, & Univ. de Sevilla. High-temperature deformation behavior in Sr TiO{sub 3} ceramics.. United States. doi:10.1016/j.jeurceramsoc.2007.02.186.
Singh, D., Lorenzo-Martin, M., Chen, G., Gutierrez-Mora, F., Routbort, J. L., Nuclear Engineering Division, and Univ. de Sevilla. Mon . "High-temperature deformation behavior in Sr TiO{sub 3} ceramics.". United States. doi:10.1016/j.jeurceramsoc.2007.02.186.
@article{osti_914805,
title = {High-temperature deformation behavior in Sr TiO{sub 3} ceramics.},
author = {Singh, D. and Lorenzo-Martin, M. and Chen, G. and Gutierrez-Mora, F. and Routbort, J. L. and Nuclear Engineering Division and Univ. de Sevilla},
abstractNote = {The high-temperature deformation behavior of a polycrystalline strontium titanate (SrTiO{sub 3}) ceramic (6 {micro}m grain size) was investigated at temperatures of 1200-1345 C in an argon atmosphere. Compressive deformation tests were conducted at strain rates ranging from 5 x 10{sup -6} to 5 x 10{sup -5} s{sup -1}. Steady-state flow stresses were 0.05-30 MPa and increased with increasing strain rates. Stress exponents of {approx}1, at temperatures >1200 C, indicated a viscous diffusion-controlled deformation with an activation energy of {approx}628 {+-} 24 kJ/mol. Comparison of activation energy with literature data suggests diffusion of cations as the rate-controlling mechanism. Absence of cavitation and grain-shape changes were consistent with grain-boundary sliding as the principal deformation mechanism. The electron back-scattered diffraction (EBSD) technique was used to determine the grain orientation as a function of applied strain. The results indicate that some of the grains rotate with cumulative rotation as large as 7 degrees at a strain of 4%.},
doi = {10.1016/j.jeurceramsoc.2007.02.186},
journal = {J. European Ceram. Soc.},
number = 11 ; 2007,
volume = 27,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

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