Effect of Sintering Parameters and Ta₂O₅ Doping on the Microstructure and Dielectric Properties of BaTiO₃ Based Ceramics

Abstract:

The main focus of the research was to correlate the composition and sintering parameters with the microstructure and dielectric properties of Ta₂O₅ (Tantalum Oxide) doped BaTiO₃ (Barium Titanate) ceramics. Ta₂O₅ was doped at three different percentages viz. 0.5, 1.0 and 1.5 mole%. The doped samples were then sintered using both single and double stage sintering techniques. Thereafter field emission scanning electron microscope (FESEM) and X-ray diffraction (XRD) techniques were used to examine the structure of the samples with particular focus on the incorporation of Ta⁵⁺ions into the BaTiO₃ crystal lattice. Finally, the dielectric properties were analyzed using impedence analyzer and the relationship between the properties and structure of doped BaTiO₃ was established. From the research, it can be stated that double stage sintering yielded best dielectric properties. The best stable value of room temperature dielectric constant (k) of 19000 was obtained for 1.5mole % Ta₂O₅ doped BaTiO₃ sample, sintered at 1320°C for 0 hour and 1280°C for 6 hours due to the combination of high percent theoretical density (%TD) and optimum grain size. At a temperature range of 30°C to 60°C, this combination of composition and sintering parameters yielded dielectric constant in the range of 18000-19000.

• Periodical: Key Engineering Materials (Volume 608)
• Pages: 247-252
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.608.247
• Online since: April 2014
• Authors: Md. Fakhrul Islam*, Rubayyat Mahbub, Adnan Mousharraf
• Keywords: Barium Titanate (BT), Ceramic, Doping, Double-Stage Sintering, Tantalaum Oxide

References

[1] Arlt, G., De With, G. and Hennings, D. 1985. Dielectric Properties of Fine-Grained Barium Titanate Ceramics. Journal of Applied Physics. 58.

DOI: 10.1063/1.336051

[41] 1619-1625.

[2] Amarande, L., Cioangher, M., Gheorghiu, A., Miclea, C., Miclea, C. F., Miclea, C. T., Spanulescu, I. And Tanasoiu, C. 2007. Microstructure and Properties of Barium Titanate Ceramics Prepared by Mechanochemical Synthesis. Romanian Journal of Information Scienceand Technology. 10.

DOI: 10.1109/smicnd.2006.283986

[4] 335-45.

[3] Kinoshinta, K. and Yamaji, A. 1976. Grain-Size Effects on Dielectric Properties in Barium Titanate. Journal of Applied Physics. 47 [I], 371-374.

DOI: 10.1063/1.322330

[4] Burfoot, J. C. and Martirena, H. T. 1974. Grain-Size Effects on Properties of Some Ferroelectrics Ceramics. Journal of Physics C: Solid State Physics. 7, 3182-3192.

DOI: 10.1088/0022-3719/7/17/024

[5] Armstrong, T. R., Buchanan, R. C., Maurice, A. K. and Morgens, L. E. 1989. Effects of Zirconia on Microstructure and Dielectric Properties of Barium Titanate. Journal of American Ceramic Society. 72.

DOI: 10.1111/j.1151-2916.1989.tb06182.x

[4] 605-611.

[6] Ahn, Y. H., Hyun, J. W., Kim, H. S., Kim, Y. J., Lee, J. H., Noh, S. J. and Yun, M. Y. 2009. Microstructural Characterization and Dielectric Properties of Barium Titanate Solid Solutions with Donor Dopants. Bulletin of the Korean Chemical Society. 30.

DOI: 10.5012/bkcs.2009.30.6.1267

[6] 1267-1273.

[7] Manalert, R. and Rahaman, M. N. 1998. Grain Boundary Mobility of BaTiO3 Doped With Aliovalent Cations. Journal of the European Ceramic Society. 18.

DOI: 10.1016/s0955-2219(97)00215-x

[8] 1063-1070.

[8] David, W. Richerson, Modern Ceramic Engineering: properties, processing and use in design, Second Edition, Marcel Dekker, New York, pp.262-264.