Effect of hydrogen on the passivation for ultra-thin 316 L SS foil

Abstract

Abstract The reformation and characterisation of the passive film formed on ultra-thin 316 L after hydrogen charging is investigated by combining EBSD, TMDS, XRD, Synchrotron-based XPS, and electrochemical experiments. The results show that ultra-thin foil reforms a passive film after 12 h of hydrogen release in NaCl solution. The reformed passive film is half the thickness of the as-received passive film and is dominated by Cr oxides/hydroxides. The lattice extension caused by residual hydrogen accelerates Cr migration to form Cr2O3; while the diffusible hydrogen occupies the cation vacancies and results in high defect density for the reformed passive film within 12 h.