Formation of iron oxides by surface oxidation of iron plate

The formation of iron oxides by surface oxidation of iron plates between 400 and 800°C for different times was monitored. Delamination of iron plates was noticed at temperatures above 500°C. The pattern morphology was dependent on the temperature of oxidation and very little on time of oxidation. Outer layers of the grown oxide consisted of hematite whereas inner layers consisted of magnetite. The surface grown oxide, formed at 800°C consisted of wüstite (dominant), hematite and subtstoichiometric magnetite (Fe_3-xO₄).