ADVANCES IN THERMODYNAMIC SIMULATION OF Al2O3-MgO CASTABLE CORROSION

ANA P. LUZ ; VICTOR C. PANDOLFELLI ; MARIANA A.L. BRAULIO; ANALÍA G. TOMBA MARTINEZ

Congreso; 55th International Colloquium on Refractories 2012; 2012

In this work, the chemical corrosion of two Al2O3-MgO castables (containing hydratable alumina or calcium aluminate cement as binder sources) was evaluated via thermodynamic calculations. Besides that, a critical analysis of three simulation models were carried out, considering: (1) the slag-castable interaction as a function of the reaction rate , (2) the changes in the slag composition due to its reaction with the castable components, assuming the direct contact between the liquid and the overall castable compositions, and (3) the slag-matrix and slag-aggregates interactions evaluated separately. The theoretical results were further compared with experimental corrosion cup-tests data. Although the thermodynamic evaluation of the overall castable compositions was able to correctly identify the phase transformations, a two-step analysis of the liquid interaction with the matrix components and later with the aggregate particles, seems to be the best alternative to predict the different corrosion performance of the two designed refractory materials.