Molten glass corrosion resistance of MoxRuySiz compounds at 1350°C in an alkali borosilicate glass

Abstract Corrosion of Mo-silicides and Mo x Ru y Si z compounds in molten glass is studied by electrochemical techniques at 1350 °C, metallographic observations (SEM) and chemical analysis (EPMA). The open circuit potential measurements (free-potential) enabled the determination of the reactions responsible for the degradation of the materials. The degradation of Mo-silicide occurs through selective oxidation of Si. Mo x Ru y Si z compounds were subjected to reactions leading to the successive oxidation of silicon and molybdenum. The progressive depletion of Si and Mo resulted in the more or less quick formation of a thick, porous and low adherent Ru-layer. Therefore, Ru-additions had no positive effect on the molten glass corrosion resistance of MoSi 2 -based materials and should even accelerate the degradation kinetics of the later through galvanic coupling.