Corrosion of High Temperature Alloys by Molten Glass

Abstract

In the glass industry, the lifetime of many metallic parts in contact with molten glass is controlled mainly by high temperature corrosion which, as for aqueous solutions is governed by oxidation-reduction reactions: reduction of glass components counterbalances the oxidation of metallic components. Depending on the glass composition, O 2 , Fe III , Si IV or other oxidants can be reduced, leading to various forms of degradation. If the corrosion potential is high enough, passivation can be observed all the more than diffusion of oxidants is accelerated. If the potential is low, active corrosion is induced. In the case where reduction of glass components leads to the formation of metals (Si, Pb, Mo...), formation of brittle intermetallic phases can be observed. The results obtained on Fe, Co, Ni, Cr as well as synthetic and commercial alloys, lead to a general description of the corrosion of refractory alloys in molten glass.