MODELAGEM TERMODINÂMICA DE ESCÓRIAS CONTENDO Ti: SISTEMAS Al2O3-TiO2 E FeO-TiO2
THERMODYNAMIC MODELING OF Ti CONTAINING SLAGS: SYSTEMS Al2O3-TiO2 AND FeO-TiO2
Siqueira, Rogério Navarro C. de; Avillez, Roberto Ribeiro; Silva, André Luiz V. da C. e
http://dx.doi.org/10.4322/tmm.00304007
Tecnol. Metal. Mater., vol.3, n4, p.40-45, 2007
Resumo
No presente trabalho, é modelado o comportamento termodinâmico dos pseudo-binários Al2O3-TiO2 e FeO-TiO2. É empregada abordagem CALPHAD, sendo a fase escória descrita pelo modelo de Kapoor-Frohberg-Gaye e os óxidos sólidos tratados como estequiométricos. Todos os cálculos foram desenvolvidos com o programa Thermocalc. A energia de Gibbs dos óxidos duplos é corrigida e a energia de Gibbs do rutilo líquido (TiO2) modificada de forma a obter uma melhor concordância com dados da literatura. Tanto para o sistema Al2O3-TiO2, quanto para o sistema FeO-TiO2 os cálculos termodinâmicos concordam em nível quantitativo com os dados experimentais disponíveis até o presente momento.
Palavras-chave
Termodinâmica computacional, Modelo de Kapoor-Frohberg-Gaye, Escórias, Dióxido de titanio
Abstract
In the present work the thermodynamic behavior of the pseudo-binaries Al2O3-TiO2 and FeO-TiO2 is assessed. The CALPHAD approach is employed, the slag phase being described by the Kapoor-Frohberg-Gaye model and all solid oxides considered stoichiometric. All calculations were conducted with the Thermocalc software. The Gibbs energy of the mixed oxides received corrections and the Gibbs energy of liquid rutile was modified for a better agreement with published data. For both systems the calculations agreed quantitatively with the experimental information available until the present date.
Keywords
Computational thermodynamics, Slag, Kapoor-Frohberg-Gaye model, Titanium dioxide
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