High-temperature annealing of ferritic stainless steel: Modification of sulfide inclusion properties and inhibition of inclusion dissolution

The effects of the annealing temperature on the electrochemical properties, anodic dissolution, and pitting corrosion resistance of MnS inclusions in 18mass％Cr ferritic stainless steel are investigated by scanning electron microscopy, macroscale polarization, and microscale polarization. The MnS inclusions in the specimens annealed at higher temperatures have higher Cr concentrations and lower Mn concentrations. The onset potential of the inclusion dissolution and the pitting corrosion resistance of the MnS inclusions increase with an increasing annealing temperature. © 2020 Japan Society of Corrosion Engineering. All rights reserved.