Modelling and experiment of selective oxidation and nitridation of binary model alloys at 700 °C – The systems Fe, 1 wt.%{Al, Cr, Mn, Si}

Selective oxidation experiments of binary iron alloys, containing 1 wt.%Al, Cr, Mn or Si were performed. Using hydrogen/water vapour mixtures adjusts low oxygen activities at the surface that hinder the formation of an outer oxide scale. This keeps the surface unchanged and generates a worst-case scenario for oxide and nitride formation inside the material. Corrosion depth and precipitate composition were observed by SEM/EDX and compared to theoretical simulations. Variations of the gas atmosphere were performed to investigate the presence of nitrides under experimental conditions. Results help to broaden knowledge of single-element effects in corrosion and the understanding of complex alloy compositions.