First-principles study on the corrosion-resistant of lead-bismuth to rough stainless steel surface

Abstract

The corrosion of lead-bismuth on steel has received much attention in ADSs. Unfortunately, the current studies are mostly based on the ideal Fe surface, but in reality, the surface of the steel is rough. In this work, the rough surface is built. By performing first-principles calculations, using adsorption and escape energies to evaluate the mechanism of dissolution corrosion on rough surfaces. The smaller adsorption energy indicates more stable adsorption properties on the rough surface for adatoms. According to the process of dissolution corrosion, the surface is more likely to be corroded. The energetics results mean that bismuth atoms are more stable on the rough surface. Combined with escape energy, rough surfaces are more susceptible to corrosion than ideal surfaces. This is further demonstrated by calculating the charge density difference of surface. Based on previous research, three alloying elements, Al, Si, and Mo, which have the best corrosion resistance, were selected for further discussion. Finally, adsorption energy is utilized to evaluate how alloy atoms affect surface dissolution corrosion. The results show that when there are four alloy atoms on the surface, the probability of Pb or Bi atom corrosion on the surface is the least.