Barium titanate grain size

Historically, materials based on doped barium titanate were used to achieve dielectric constants as high as 2,000 to 10,000. The high dielectric constants result from ionic polarization and the stress enhancement of k associated with the fine-grain size of the material. The specific dielectric properties are obtained through compositional modifications, ie, the inclusion of various additives at different doping levels. For example, additions of strontium titanate to barium titanate shift the Curie point, the temperature at which the ferroelectric to paraelectric phase transition occurs and the maximum dielectric constant is typically observed, to lower temperature as shown in Figure 1 (2). 

Frey, M.H. et al. (1998) The role of interfaces on an apparent grain size effect on the dielectric properties for ferroelectric barium titanate ceramics, Ferroelectrics, 206-207, 337-53. 

Frey MH, Payne DA (1996) Grain-size effect on structure and phase transformations for barium titanate. Phys Rev 6 54 3158-3168... 

Curecheriu L, 6uscagha MT, 6uscagha V et al (2010) Grain size effect on the nonlinear dielectric properties of barium titanate ceramics. Appl Phys Lett 97 242909... 

Kinoshita, K. and Yamaji, A. (1976) Grain size effect on dielectric properties in barium titanate. J. Appl. Phys., 47, 371-373. 

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