%0 Journal Article
%T Influence of rare-earth additives (La, Sm and Dy) on the microstructure and dielectric properties of doped BaTiO3 ceramics
%A Paunovi£¿ Vesna
%A £¿ivkovi£¿ Lj.
%J Science of Sintering
%D 2010
%I International Institute for the Science of Sintering, Beograd
%R 10.2298/sos1001069p
%X A series of La/Mn, Sm/Mn and Dy/Mn codoped BaTiO3 samples were prepared by the conventional solid state procedure with dopant concentrations ranging from 0.1 up to 2.0 at%. The specimens were sintered at 1320¡ãC and 1350¡ãC in an air atmosphere for two hours. The low doped samples demonstrated a mainly uniform and homogeneous microstructure with average grain sizes ranging from 0.3 ¦Ìm to 5.0 ¦Ìm. The appearance of secondary abnormal grains in the fine grain matrix and core-shell structure were observed in highly doped La/BaTiO3 and Dy/BaTiO3 sintered at 1350¡ãC. The low doped samples, sintered at 1350¡ãC, display a high value of dielectric permittivity at room temperature, 6800 for Sm/BaTiO3, 5900 for Dy/BaTiO3 and 3100 for La/BaTiO3. A nearly flat permittivity-response was obtained in specimens with 2.0 at% additive content. Using a modified Curie-Weiss law the Curie-like constant C  and a critical exponent ¦Ã were calculated. The obtained values of ¦Ã pointed out the diffuse phase transformation in heavily doped BaTiO3 samples.
%K batio3 doped ceramics
%K sintering
%K microstructures
%K dielectric properties
%U http://www.doiserbia.nb.rs/img/doi/0350-820X/2010/0350-820X1001069P.pdf