Stainless Steel Surface Structure and Initial Oxidation at Nanometric and Atomic Scales

Main Authors: Li, Ma, Wiame, Frédéric, Maurice, Vincent, Marcus, Philippe
Format: info publication-preprint Journal
Bahasa: eng
Terbitan: , 2019
Subjects:
Online Access: https://zenodo.org/record/3345595
Daftar Isi:
  • The durability of passivable metals and alloys is often limited by the stability of the surface oxide film, the passive film, providing self-protection against corrosion in aggressive environments. Improving this stability requires to develop a deeper understanding of the surface structure and initial surface reactivity at the nanometric or atomic scale. In this work we applied scanning tunneling microscopy to unravel the surface structure of a model stainless steel surface in the metallic state and its local modifications induced by initial reaction in dioxygen gas. The results show a rich and complex structure of the oxide-free surface with reconstructed atomic lattice and self-organized lines of surface vacancies at equilibrium. New insight is brought into the mechanisms of initial oxidation at steps and vacancy injection on terraces leading to Cr-rich oxide nuclei and locally Cr-depleted terraces, impacting the subsequent mechanism of chromium enrichment essential to the stability of the surface oxide.