Effect of temperature and loading mode on environmentally assisted crack growth of a forged 316L SS in oxygenated high-temperature water

• Corrosion fatigue crack growth rate increases with increasing temperature.
• Stress corrosion crack growth rate increases with increasing temperature.
• Stress corrosion crack is activated by periodic unloading and reloading.

The crack growth rates (CGRs) of a forged nuclear grade 316L SS piping material were measured at various temperatures and loading modes in oxygenated high-temperature water. A direct current potential drop technique was used to monitor the CGRs throughout the tests. The fracture surface of crack advance under stress corrosion conditions exhibited typical intergranular stress corrosion cracking characteristics. CGRs increased monotonically with increasing temperature. CGRs under trapezoidal waveform loading were moderately higher than those under constant K loading.