Abstract
Experiments have been carried out on 1T-CT and 1T-WOL crack growth specimens of mill annealed SUS 316L (Type 316L) stainless steel to examine the IGSCC susceptibility of non sensitized stainless steel in 288°C water. SUS 316L stainless steel was mill annealed at 1100°C for 10min. Intergranular crack growth was detected on the SUS 316L stainless steel specimen in water containing 0.2ppm O2 and conductivity of 0.5μS/cm, and the crack growth rate of this material was about a factor of 10 lower than that of a sensitized SUS 304 stainless steel. Crack growth was not detected, however, on the specimen tested in 0.1μS/cm conductivity water. Intergranular attack was also found out in creviced region of SUS 316L specimen in 0.5μS/cm conductivity water, and clear intergranular morphology was observed by scanning electron microscopy after Streicher test. On the other hand, intergranular attack in creviced region and intergranular morphology after Streicher test were not taken on mill annealed SUS 304L stainless steel. Molybdenum included in SUS 316L stainless steel seemed to play a rule in acceleration of intergranular corrosion in relatively high conductivity water condition.
