Insight into scale transformation and internal oxidation mechanism of hot rolled Si Mn added high strength steel

In our previous research, the hot-rolled coiling process method for producing surface pure Fe was thoroughly explored. This study uses vacuum sealing heat treatment to determine the impact of temperature and soaking time on the internal oxidation of C-Mn-Si steel after hot rolled coiling. The results show a clear relationship between the internal oxidation in hot rolling and the microstructure transformation of the surface oxide scale. By carefully analyzing the cross-microstructure section using FIB/TEM, it was discovered that the behavior of the alloying components Si and Mn in the internal oxidation differed. The generating mechanism of internal oxidation in hot rolling was explored using the three steps of oxygen pressure reduction, and the phase transformation in the reaction process was examined using thermodynamic calculations.