Materials Research Bulletin, Vol.72, 123-132, 2015
Calcium titanate (CaTiO3) dielectrics prepared by plasma spray and post-deposition thermal treatment
This paper studies calcium titanate (CaTiO3) dielectrics prepared by plasma spray technology. A water stabilized plasma gun (WSP) as well as a widely used gas stabilized plasma gun (GSP) were employed in this study to deposit three sample sets at different spray conditions. Prepared specimens were annealed in air at atmospheric pressure for 2 hat various temperatures from 530 to 1170 degrees C. X-ray diffraction (XRD), Raman spectroscopy and porosity measurements were used for sample characterization. Dielectric spectroscopy was applied to obtain relative permittivity, conductivity and loss factor frequency dependence. Band gap energy was estimated from reflectance measurements. The work is focused on the explanation of changes in microstructure and properties of a plasma sprayed deposit after thermal annealing. Obtained results show significant improvement of dielectric properties after thermal annealing. (C) 2015 Elsevier Ltd. All rights reserved.