High temperature oxidation behaviour of Fe-15.7 wt.% Cr-8.5 wt.% Mn in oxygen without and with water vapour at 700 ℃

摘要

Fe-15.7 wt.% Cr-8.5 wt.% Mn was oxidised in O-2 and O-2-9 vol.% H2O at 700 degrees C. Oxide scales in both atmospheres consisted of M2O3 and M3O4 where M could be Mn, Cr and Fe. The graphical representation of the water vapour effect on the concentrations and dominant regimes of defects in the Brouwer diagram was proposed. The enhanced oxidation rate due to water vapour was found possibly as a result of the increased metal vacancy concentration and its dominant regime and the inwards diffusion of hydroxyl ions supported by the scale adhesion results.