Effects of Heat Treatment on Microstructure and Pitting Corrosion Resistance of 2205 Duplex Stainless Steel

Abstract

In this study, the effect of heat treatment processes on microstructure and pitting corrosion resistance of 2205 duplex stainless steel within the temperature range of 500C~650C was investigated. According to TEM analysis, intermediate phase and R phase begin to precipitate after aging 48h at 590 °C and ϭ phase begins to precipitate after aging 5h at 650 °C The anodic polarization results show that the pitting resistance of samples was reduced both at aging temperatures of 590°C and 650°C The results also indicate that the precipitation of intermediate phase obviously decreased the pitting corrosion resistance of 2205 duplex stainless steel. In addition, it was observed that the pits inclined to nucleate and grow near the precipitations in the ferrite and a/y interface boundary.