SCC growth behaviors of austenitic stainless steels in simulated PWR primary water

Evaluation of stress corrosion cracking susceptibility of forged 316 stainless steel in simulated primary water

“…Larger values of n correspond to higher K dependence of CGR. According to the data obtained in this study, the n values of A and B are calculated as 1.5 and 1.2, respectively, which are similar to the n values of 1.5 for 20% cold‐worked 316 stainless steel in hydrogenated water observed by Arioka et al However, the n values of the forged 316 stainless steel are lower than that of 1.7 for 20% cold‐worked 316 stainless steel in hydrogenated high temperature water reported by Terachi et al and that of 2.3 for 20% cold‐worked 316L stainless steel in oxygenated high temperature water reported by Andresen et al A lower K dependence is expected in more susceptible materials and more severe environments . The n value of the forged 316 stainless steel is relatively lower because of the severe deformation and oxygenated water chemistry .…”

“…However, both laboratory investigations and field experience have revealed that the SCC susceptibility of Fe‐Ni‐Cr alloys in high temperature water is increased because of the work‐hardening induced by material deformation . Much research has focused on the SCC behaviors of cold‐rolled 316 stainless steels . However, the SCC behaviors of forged 316 stainless steel have not yet been studied systematically in high temperature water.…”

Prediction of primary water stress corrosion crack growth rates in Alloy 600 using artificial neural networks

“…As can be seen from the figure, Q decreases from 239 kJ/mol to 183 kJ/ mol and then to 95 kJ/mol when the yield strength increases from 300 MPa to 340 MPa and then to 389 MPa, respectively. Estimated thermal activation parameters always include CGR measurement errors, but the trend of an apparent activation parameter decrease with increasing yield strength or extent of cold work has been reported by Rebak [40], Moshier and Brown [41], Terachi [42], and Cassagne and Gelpi [43]. An alloy is cold-worked when it is deformed plastically at temperatures that are low relative to its melting point.…”

“…[18]. The CGR is generally induced by the applied stress intensity factor (K I ) and the apparent K I dependence of the CGR is often empirically described by the following relation [42,53]:…”

Effects of Grain Orientation on Stress State near Grain Boundary of Austenitic Stainless Steel Bicrystals

“…Researches have shown that the initiation of IGSCC in nickel alloys in high-temperature water greatly depends on inclination of the grain boundary (GB) to the tensile axis [13]; the cracks tend to be initiated easily at the GB whose inclination is perpendicular to the tensile axis and suggested that the local stress perpendicular to the GB governs the cracking behavior; this result seems to be consistent with the theory. However, other experiments and observations show that cracks could travel in different directions, such as at an angle perpendicular or even parallel to the applied load [14][15][16].…”