Corrosion of refractory materials by a container glass melt under the influence of various convection flows Comparison between theory and experiment

Abstract

Corrosion measurements on various refractory materials in a container glass melt under the action of three types of convection flow which were reported during the last few years will be discussed under fundamental aspects and a comparison between theory and experiment will be given. For that reason all relevant physical and chemical properties of the xystems refractories-glass melt are reported. This allows to calculate the most complex property in those systems: the effective diffusion coefficient, Deff. The main results are: first, Deff is independent of the type of the three convection flows (forced, density and interfacial convection flow) indicating good agreement between theory and experiment. Second, Deff depends on the type of refractory materials: those which contain barriers for diffusion and solubility (sieve-structure of baddeleyite or solid solution of chromia and alumina) show the lowest Deff values. Third, in addition to the temperature dependence the concentration dependence of viscosity has to be considered also. Fourth, the concentration profile of the melt within the meniscus in the case of interfacial convection flow plays a certain role and seems to be temperature-dependent.