Three examples of high-temperature corrosion of metals by molten glasses

The effects of glass redox, glass basicity and glass temperature on the metallic material corrosion in molten glass are illustrated with regard to three examples. a) The corrosion of a platinum alloy immersed in a Te-bearing glass under reducing conditions is due to the formation of low melting temperature PtxTe1-x compounds. b) The corrosion of a Ni-base superalloy immersed in a Mo-bearing glass in a reducing atmosphere is due to the dissolution of the chromia protective scale. Indeed the cathodic reaction (Mo(VI)lozenge Mo-III) generates O2- ions which can promote the basic dissolution of Cr2O3. c) The corrosion of a Co-base superalloy in molten C-glass is investigated as a function of temperature, yielding to the demonstration of the existence of a maximum using temperature, characterized by a passive-to-active state transition.