Fractographic Study of Stress Corrosion Cracking Mechanism in Duplex Stainless Steel

Abstract

The mechanism of stress corrosion cracking (SCC) of duplex stainless steel, SUS 329J1 was investigated in 42% MgCl₂ aq. sol. (416K) by studying the effect of structural anisotropy on SCC. It was made clear that SCC was more pronounced in the case of crack growth being parallel to the main rolling direction than in other cases, and cracks tended to propagate along α phase than γ phase. The high SCC resistance of SUS 329J1 duplex stainless steel seems to be caused by cathodic protection of γ phase for α phase.