Effect of "475°C embrittlement" on the corrosion behaviour of grade 2205 duplex stainless steel investigated using local probing techniques


Örnek C., Engelberg D., Lyon S., Ladwein T.

European Corrosion Congress, EUROCORR 2013, Estoril, Portugal, 1 - 05 September 2013 identifier

  • Publication Type: Conference Paper / Full Text
  • City: Estoril
  • Country: Portugal
  • Istanbul Technical University Affiliated: No

Abstract

The work reported in this paper correlates microstructure development after low temperature embrittlement heat treatments with pitting corrosion susceptibility in grade 2205 duplex stainless steel. Heat-treatments at 475°C for up to 255 hours were carried out and microstructures characterised using scanning electron microscopy (SEM) and micro-hardness testing. Local electrochemical measurements using an electrochemical micro-cell were carried out and the critical pitting temperature (cPT) determined. Short-duration heat treatments for up to 10 hours showed an increase in CPT, attributed to an improved electrochemical character of the ferrite. Long-term heat treatments (>50 hours) indicated a decrease in CPT due to the precipitation of other precipitates and the formation of elemental depletion zones.