Scale growth on 2·25Cr–1 Mo steel

A 2·25Cr–1 Mo steel was oxidised at 600°C in dry flowing oxygen for periods of up to 100 h. The change in the structure of the oxide scale with time was studied thermogravimetrically and microstructurally by use of SEM and EDX analyses. It was shown that an oxide layer of Fe3O4 nucleated and spread laterally between layers of α-Fe2O3 and a doped spinel oxide.MST/931