Quantification of Calcium Titanate (CaTiO3 ) by the Rietvield Method in Different Molar Proportions
Resumo
O objetivo do presente estudo é produzir titanato de cálcio (CT) com estrutura perovskita (ABO3 ) a partir de rutilo comercial (TiO2 ) e carbonato de cálcio comercial (CaCO3 ). As matérias-primas foram caracterizadas por difração de raios X (DRX). Diferentes composições foram formuladas, as amostras foram comprimidas a 150 MPa e sinterizadas em forno resistivo a temperaturas de 1300 °C por 3h. As amostras foram analisadas por DRX após o processo de sinterização e as fases foram quantificadas de acordo com o método de Rietveld. As imagens foram representadas por meio de microscopia eletrônica de varredura (MEV), a fim de mostrar as características das microestruturas formadas. A densidade dos pellets sinterizados foi medida usando o método de Arquimedes. De acordo com os resultados, a formação do CT depende da razão molar entre os cátions cálcio e titânio nas composições analisadas.
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