Table of Contents
ISRN Ceramics
Volume 2012 (2012), Article ID 943734, 6 pages
http://dx.doi.org/10.5402/2012/943734
Research Article

Impedance and Electrical Modulus Study of Microwave-Sintered S r B i 2 T a 2 O 9 Ceramic

1Department of Physics, National Institute of Technology, Orissa, Rourkela 769008, India
2Department of Physics, C. V. Raman College of Engineering, Orissa, Bhubaneswar 752054, India
3Department of Physics, National Institute of Technology, Tamilnadu, Tiruchirapalli 620015, India

Received 6 December 2011; Accepted 9 January 2012

Academic Editors: Y. Laosiritaworn, A. Ravaglioli, and M. F. Zawrah

Copyright © 2012 V. Senthil et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Bismuth layered structure SrBi2Ta2O9 ceramic is prepared by the microwave sintering technique via solid state route at 1100°C for 30 mins. X-ray diffraction analysis is used to analyze the phase purity, which identifies the orthorhombic structure with A21am space group. The fracture surface of the sintered pellet is visualized by scanning electron microscopy. Impedance spectroscopy is used to analyze the sample behavior as a function of frequency and temperature. Impedance and modulus study reveals the temperature-dependent non-Debye type relaxation phenomenon. The Nyquist plot shows a single arc representing the grain effect in the material, and the conductivity increases with increase in temperature. The Nyquist plot is fitted with an equivalent circuit, and the simulated parameters are well agreed with the calculated parameters. Arrhenius plot shows two different activation energies at below and above 300°C which identifies the phase transition of SrBi2Ta2O9 ceramic. The fatigue property is explained by the basis of activation energies, which shows that SBT sintered by microwave technique is more fatigue resistant than conventional sintering.