Interfacial corrosion behavior between O atoms and alloy elements at iron-liquid LBE interface by first-principles molecular dynamics

The interfacial corrosion behavior between LBE adding O atoms and Fe substrate surface containing alloy ele-ments (Cr, Ni, Al, Si) has been studied by first-principles molecular dynamics simulations. Theoretical calcula-tions show that the O atoms in liquid LBE could form the protective oxide layer with the alloy elements (Cr, Al, Si) on the Fe substrate surface at the iron-liquid LBE interface, in which slows down the corrosion process. The estimated mean effective potential energy path suggests that breaking the O-Si bond requires the highest energy barrier of 0.61 eV among the doped elements. Besides, the diffusion coefficient shows that Si atom has the lowest value of 0.277 x 10-5 cm2/s, which indicated that adding doped-Si atoms can effectively slow down the corrosion process of the steel. In addition, the diffusion coefficient of Pb, Bi and O atoms in this work is much lower compared with the previous work, indicating that the oxide layer formed at the iron-liquid LBE interface can effectively improve the corrosion resistance of the steel. In a word, this work is instructive for a deeper understanding of corrosion mechanism and provides valuable information for the performance evaluation and material design of the steel under reactor conditions.