SS316L stainless steel is one of the important structural materials for the in-core components and pressure boundaries of the advanced boiling water reactors (ABWR). This work was mainly focused on the effects of strain amplitude and fatigue frequency on the low-cycle fatigue (LCF) behavior of SS316L stainless steel in a high temperature, high pressure water environment. The test results show the fatigue life is significantly increased with decreasing the strain amplitude. The specimens remain intact after being fatigue-tested up to 5 X 10~5 cycles, when the applied strain amplitude is no greater than 0.12 percent. During the early stage of the low-cycle fatigue test, the cyclic hardening phenomenon was observed. The results from the tests of frequency effect show the lower the fatigue frequency was applied, the shorter the specimen fatigue life was observed. The steel specimens have the longest fatigue life when tested in air at room temperature, but, in contrast, they were observed to have the shortest one when tested in the high temperature, high pressure water environment. From the above observations, it can be inferred that the fatigue-corrosion interaction plays a significant role in determining the fatigue life of SS316L stainless steel. SEM fractographic examinations reveal that a large quantity of granular corrosion products were desposited on the fracture surface of the specimen tested in an aqueous environment, but that none was observed with the specimen tested in air. The EDS analysis shows the corrosion products are mainly composed of Fe, Cr, Ni and oxygen. They appear different from the second-phase particles which are rich with S, Mn elements
SS316L stainless steel low-cycle fatigue strain amplitude frequency high temperature and high pressure water