Determination of threshold stress intensity for chloride stress corrosion cracking of solution-annealed and sensitized austenitic stainless steel by circumferential notch tensile technique

This paper discusses a new approach to determination of threshold stress intensity factor for stress corrosion cracking (KISCC) of stainless steel in 42% MgCl2 environment at 154 deg. C. KISCC of solution-annealed and sensitized AISI 304 stainless steel in chloride environment has been determined using circumferential notch tensile (CNT) technique. KISCC data generated using CNT technique have been compared with those generated using traditional techniques such as compact tension and double cantilever beam (reported in the literature). The results presented here validate the ability of CNT technique for determination of KISCC of sensitized as well as solution-annealed austenitic stainless steel. This paper also discusses the mechanistic aspects of the difference in fractographic features of the sensitized and solution-annealed stainless steel.