Title :
Grain size effects in barium titanate
Author :
Gachigi, K. Wa ; Kumar, U. ; Dougherty, J.
Author_Institution :
Pennsylvania State Univ., University Park, PA, USA
fDate :
30 Aug-2 Sep 1992
Abstract :
Grain size effects in CBaTiO3 are examined as a function of porosity in order to evaluate the effect of microstructurally imposed stresses on the dielectric behavior. Hydrothermal starting powder was used to minimize any extraneous effects. Fast firing techniques were used to obtain a variety of grain sizes and densities, and the data were evaluated using an analysis of the Curie-Weiss behavior. A percolation limit between 48% and 60% of theoretical density is proposed below which insufficient flux continuity is thought to limit the dielectric response of the ceramic. Above this limit, increased density appears to increase the room-temperature dielectric constant for grain sizes between approximately 0.6 μm and 20 μm
Keywords :
barium compounds; ceramics; dielectric losses; ferroelectric Curie temperature; ferroelectric transitions; grain growth; grain size; percolation; permittivity; porosity; 0.6 to 20 micron; CBaTiO3; Curie temperature; Curie-Weiss behavior; dielectric behavior; dielectric loss; dielectric response; firing techniques; grain density; grain growth; grain sizes; hydrothermal powder; microstructurally imposed stresses; percolation limit; porosity; room-temperature dielectric constant; Area measurement; Barium; Dielectrics; Energy measurement; Grain size; Impurities; Powders; Surface treatment; Temperature distribution; Titanium compounds;
Conference_Titel :
Applications of Ferroelectrics, 1992. ISAF '92., Proceedings of the Eighth IEEE International Symposium on
Conference_Location :
Greenville, SC
Print_ISBN :
0-7803-0465-9
DOI :
10.1109/ISAF.1992.300583
