Author:

Keywords:

Science & Technology, Physical Sciences, Physics, Condensed Matter, Physics, Inclusions, Pitting corrosion, Rare earth Ce, First principle, LOW-CARBON STEEL, MAGNETIC-PROPERTIES, BEHAVIOR, METALS, CERIUM, MICROSTRUCTURE, ADSORPTION, MORPHOLOGY, TITANIUM, 0204 Condensed Matter Physics, 0206 Quantum Physics, 0303 Macromolecular and Materials Chemistry, General Physics, 5104 Condensed matter physics

Abstract:

© 2019 The mechanism of inclusion-induced initial pitting corrosion of Al-Ti-Ca complex deoxidized steel with Ce treatment was studied by the experimental investigation and theoretical calculation. To figure out which phases of complex inclusion containing different components induced initial pitting corrosion, the scanning electron microscope (SEM) analysis, the continuous immersion experiments and density functional theory (DFT) calculation were conducted. Two types of inclusions and different pit morphologies were observed. The pit initially occurred at the sulfide inclusions (MnS and Ce 2 O 2 S) rather than the steel matrix due to the lower the electronic work function (EWF) of this compound compare to the steel matrix and other phases. In addition, the Ce-rich inclusion possessed the higher pitting corrosion resistance than the same type of inclusions. Finally, a schematic diagram was established to explain the mechanism of the different inclusions in initiating and proceeding pitting corrosion.