Local residual stresses in pressure-treated barium titanate powders probed by inelastic light scattering

ABSTRACT

Properties of the barium titanate submicron powder treated by high pressure were studied by Raman scattering. Residual mechanical stresses were estimated to be about 2 GPa in barium titanate powder treated under uniaxial pressure of 4 GPa. It is supposed that these mechanical fields change the characteristics of the central peak of the Raman spectra in the low frequency part. It is shown that central peak in pressure-treated powder corresponds to a broad distribution of relaxation times. Such behavior is typical for relaxors known as materials with the compositional disorder. Annealing decreases the residual mechanical stresses.

KEYWORDS:

• Barium titanate
• Raman scattering
• central peak
• ferroelectric phase transition

Funding

This work was supported by Russian Foundation for Basic Research (Grants Nos. 15-02-04950 and No. 14-02-00189) and Ministry of Education and Science of the Russian Federation (Research projects No. 2132 and 3.1246.2014/K).