Secondary corrosion protection of FeCr(Al) model alloys at 600 °C – The influence of Cr and Al after breakaway corrosion

Journal article, 2021

The influence of Cr and Al content on the oxidation behaviour of FeCr(Al) model alloys after breakaway oxidation at 600 °C and the underlying mechanisms were investigated in detail with thermogravimetrical analysis (TGA), thermodynamic calculations and advanced electron microscopy. The results showed that a Cr-content of ≥18 wt% drastically reduced the growth rate of the Fe-rich oxide scale, formed after breakaway oxidation, for FeCrAl alloys but not for FeCr alloys. This was attributed to the ability of the Fe(18-25)CrAl alloys to prevent internal oxidation, which enables the formation of a healing layer.