Effect of C Fraction on Corrosion Properties of High Interstitial Alloyed Stainless Steels

The effects of carbon fraction on various corrosion properties of Fe18Cr10MnNC alloys were investigated. The alloys contained 0.6 wt pct of nitrogen and carbon, and the carbon fraction varied from 0.03 to 0.47. With increasing the carbon fraction, corrosion potential raised, critical dissolution rate decreased, and pitting potential increased. The high carbon fraction was responsible for high resistance against intergranular corrosion of the alloys aged at 1123 K (850 °C) for 100 seconds. But after aging at 1123 K (850 °C) for 600 seconds, the intergranular corrosion accelerated with increasing the carbon fraction.