First-principles calculation of the resistance to lead-bismuth eutectic corrosion on Fe (111) surface of austenitic stainless steel

Abstract

The corrosion of liquid metal atoms on the iron surface plays a vital role in the life of the reactor. We use density functional theory (DFT) to study the adsorption energy of Pb and Bi atoms on the Fe (111) surface and the escape energy of Fe atoms on the surface. The adsorption effects of Pb and Bi atom at the fcc site are the best, and the adsorption energies are −2.66 eV and −3.07 eV, respectively. It shows that Bi is more easily adsorbed on the Fe surface than Pb, which is consistent with the experimental phenomena. The escape energies of Fe atoms on clean surface and adsorbed Pb (Bi) surface are 5.11 eV and 4.58 (4.56) eV, respectively, indicating that the adsorption of Pb and Bi on clean Fe (111) surface makes Fe escape more easily. The influence of other alloying elements in steel (Cr, Ni, Ti, Mo, Mn, Si and Al) on corrosion behavior is also studied. The results show that these seven alloying elements all have an inhibitory effect on the adsorption effect of Pb and Bi, thereby weakening the corrosion, but their effects on the escape of Fe are different. Combining the two energies to obtain the total energy (Etot), it shows that both Si and Cr can reduce the dissolution corrosion of steel in LBE.