Dew-point controlled oxidation of Fe–C–Mn–Al–Si–Cu transformation-induced plasticity-aided steels

Oxides formed during the dew-point control process were investigated in the Fe–C–Mn–Si–Al–Cu alloy steel. Al2O3, MnAl2O4, AlN and multi-layered Al–O/Mn–Si–O oxides were identified. Alloyed aluminum formed Al–O oxide to block incoming oxygen from the surface. The cored structure of Al–O and Mn–Si–O oxides revealed that the oxide formation was partially governed by the kinetic process. MnAl2O4 was formed at the surface of AlN when the duration in the controlling gas was extended.