Oxidation behavior of Sodium-, Calcium- and Potassium- Sulphates coated Fe-20Cr alloy at 800°C

Abstract

The effect of Na2S04, CaS04,K2S04 and their mixture coatings on the high temperature oxidation behaviour of Fe-20Cr alloy at 800 C has been investigated. The data have been complemented by kinetic measurements, SEM observations and X-ray diffraction analysis. The accelerated oxidation of the alloy coated with mixtures are observed due to the formation of alkali iron trisulphates. The alkaline earth sulfates have deleterious effect on the protectivity of the scales and rapid degradation of the alloy is noted.