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Journal of Advanced Ceramics  2014, Vol. 3 Issue (1): 17-30    doi: 10.1007/s40145-014-0089-x
Research Article     
Effect of sintering temperature on microstructure and electrical properties of Sr1-x(Na0.5Bi0.5)xBi2Nb2O9 solid solutions
Hana NACEUR*,Adel MEGRICHE,Mohamed EL MAAOUI
Laboratory of Applied Mineral Chemistry, Department of Chemistry, Faculty of Sciences, University Tunis ElManar, Campus 2092, Tunis, Tunisia
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Abstract  

In this study, we investigated the effect of sintering temperature on densification, grain size, conductivity and dielectric properties of Sr1-x(Na0.5Bi0.5)xBi2Nb2O9 ceramics, prepared by hydrothermal method. Pellets were sintered at different temperatures. Density increased with sintering temperature, reaching up to 96% at 800 ℃. A grain growth was observed with increasing sintering temperature. Impedance spectroscopy analyses of the sintered samples at various temperatures were performed. Increase in dielectric constant and in Curie temperature with sintering was discussed. Electrical conductivity and activation energy were calculated and attributed to the microstructural factors.



Key wordsceramics      sintering      light scattering      dielectric properties     
Received: 13 September 2013      Published: 10 June 2014
Corresponding Authors: Hana NACEUR   
Cite this article:

Hana NACEUR,Adel MEGRICHE,Mohamed EL MAAOUI. Effect of sintering temperature on microstructure and electrical properties of Sr1-x(Na0.5Bi0.5)xBi2Nb2O9 solid solutions. Journal of Advanced Ceramics, 2014, 3(1): 17-30.

URL:

http://jac.tsinghuajournals.com/10.1007/s40145-014-0089-x     OR     http://jac.tsinghuajournals.com/Y2014/V3/I1/17

Fig. 1 Sintered density percentage as function of sintering temperature for Sr1-x(Na0.5Bi0.5)xBi2Nb2O9 solid solutions.
Fig. 2 Sintered density percentage as function of sintering duration at 840 ℃ for Na0.5Bi2.5Nb2O9 ceramic.
Fig. 3 Densification factor as function of sintering temperature for Sr1-x(Na0.5Bi0.5)xBi2Nb2O9 solid solutions.
Fig. 4 Thickness shrinkage percentage as function of sintering temperature for Sr1-x(Na0.5Bi0.5)xBi2Nb2O9 solid solutions.
Fig. 5 Diameter shrinkage percentage as function of sintering temperature for Sr1-x(Na0.5Bi0.5)xBi2Nb2O9 solid solutions.
Fig. 6 Mean grain size as function of sintering temperature for Sr1-x(Na0.5Bi0.5)xBi2Nb2O9 solid solutions.
Fig. 7 Logarithm of average grain versus reciprocal of sintering temperature for Sr1-x(Na0.5Bi0.5)xBi2Nb2O9 solid solutions.
Fig. 8 Activation energy of grain growth as function of composition.
Fig. 9 Dielectric constant as function of sintering temperature for Sr1-x(Na0.5Bi0.5)xBi2Nb2O9 solid solutions.
Fig. 10 Curie temperature as function of sintering temperature for Sr1-x(Na0.5Bi0.5)xBi2Nb2O9 solid solutions.
Fig. 11 Electrical conductivity as function of temperature at different sintering temperatures for Sr1-x(Na0.5Bi0.5)xBi2Nb2O9 solid solutions.
Fig. 12 Arrhenius plots of electrical conductivities as function of temperature for Sr1-x(Na0.5Bi0.5)xBi2Nb2O9 solid solutions.
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