Effects of Aluminium Contents and Consolidation Techniques on Chemical Composition, Microstructure and Dielectric Properties of Strontium Titanate

Abstract:

It has been accepted that compositions and microstructures significantly affected dielectric properties of materials. In general, chemical compositions were influenced by additive contents, while consolidation techniques controlled microstructure of the materials to have appropriate grain sizes. This study, therefore, aimed at examining effects of aluminium contents and consolidation techniques on chemical compositions and microstructures of the strontium titanate. Experimental results revealed that at higher aluminium contents, only small quantities of TiO 2 secondary phase were present, while grain sizes generally decreased. The results also indicated that the cold isostatic pressing technique led to high sintered density. The greatest dielectric constant (281.5 at 1 MHz) obtained in this study was achieved in strontium titanate sample with 30 at% of Al addition, pressed by cold isostatic pressing. Enhancement of dielectric constant of the sample was attributed to low secondary phase, fine grain sizes and high sintered density.

• Periodical: Key Engineering Materials (Volume 751)
• Pages: 403-409
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.751.403
• Online since: August 2017
• Authors: Jednupong Palomas, Oratai Jongprateep*
• Keywords: Aluminium Additions, Dielectric Properties, Solution Combustion Technique, Strontium Titanate

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