The Role of Silicon in Maintaining Protective Oxidation in a 20%Cr Austenitic Stainless Steel to High Temperatures

This paper studies the role of silicon in the prevention of non-protective oxidation in 20%Cr/25%Ni/Nb stabilised stainless steel in CO₂-based gas at 1000°C, using alloy silicon contents in the range 0 to 2.25 wt%. The kinetics of oxidation are studied using gravimetric methods and the morphology of the oxide scale is examined using techniques that include optical and scanning electron microscopy and electron probe microanalysis.