Chromia-forming steels are excellent candidates to resist to high temperature oxidizing
atmospheres because they form protective oxide scales. The oxide scale growth mechanisms are
studied by exposing AISI 304 stainless steel to high temperature conditions in air, and the analyses
were carried out by means of thermogravimetry and in situ X-rays diffraction. The in situ XRD
analyses carried out during high temperature AISI 304 steel oxidation in air reveals the accelerated
growth of iron-containing oxides such as hematite Fe2O3 and iron-chromite FeCr2O4, when the
initial germination of the oxide layer contains the presence of a manganese-containing spinel
compound (1000°C). When the initial growth shows the only chromia formation (800°C), hematite
formation appears differed in time. Protection against corrosion is thus increased when the initial
germination of manganese-containing spinel oxide is inhibited in the oxide scale.
