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In order to build bulk pieces using the slip casting technique, barium stannate (BaSnO3) ceramic powders were synthesized using two chemical methods (controlled precipitation and Pechini). Differences in the electrical behavior of the pieces, depending on the synthesis method employed, were then determined. For the analysis, a stable suspension of the synthesized ceramic powder (or 57.6% solids slip) was obtained using water as solvent; the slip was poured into a mold to produce parallelepiped shaped green pieces. The electrical behavior in air at 300 C was determined for pieces sintered using a range of temperatures. The results of this electrical characterization showed that the method of synthesis has strong effects on the electrical behavior of the sintered samples Fil: Ochoa Muñoz, Yasser Halil. Universidad de Cauca; Colombia Fil: Schipani, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Aldao, Celso Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Ponce, Miguel Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Savú, Raluca. Universidade Estadual de Campinas; Brasil Fil: Rodriguez Paez, Jorge Enrique. Universidad de Cauca; Colombia

The effects of Co[sub 3]O[sub 4] and Sb[sub 2]O[sub 3] in the ZnO-Bi[sub 2]O[sub 3] sintering process have been studied by several researchers. However, some aspects of their influence on ZnO-Bi[sub 2]O[sub 3] sintering behavior, which are important for the characteristics of ZnO varistors, such as the phase distribution, are still not well understood. Aiming to a better comprehension of the involved phenomena, the authors have studied the thermal and physicochemical behavior of the ZnO-Bi[sub 2]O[sub 3] system during the sintering process (crystalline phases formed, evaporation and decomposition reactions), by thermogravimetric analysis, scanning electron microscopy and x-ray diffraction. Thermogravimetric analysis shows a weight loss of the samples during the sintering process. They show that this weight loss is a consequence of Bi[sub 2]O[sub 3] evaporation. Experimental results indicate that the pyrochlore phase restrains the bismuth oxide evaporation. At temperatures higher than 950 C the pyrochlore reacts with ZnO and then the weight loss and the grain growth rate increase.