Sustainable Development Goals

Abstract/Objectives

To improve the oxidizing water environment in a light-water SMR, reducing agents are added to mitigate stress corrosion cracking (SCC) of 304L stainless steel and XM-19 stainless steel. To have a better understanding to the SCC of the 304L SS and XM-19 stainless steel, the SCC growth behavior was investigated via slow strain rate tensile (SSRT) tests in 288oC and high-pressure pure water environment containing a fixed concentration of reducing agent. The effects of two corrosion mitigation techniques including hydrogen injecting or alcohol adding on the inhibition of stress corrosion cracking were investigated.

Results/Contributions

XM-19 retains higher strength following SA and SEN treatments under dissolved oxygen conditions, with ductility further enhanced at elevated solution annealing temperatures. The oxide films formed on both materials are predominantly composed of NiFe₂O₄. Fractographic analysis indicates that XM-19 exhibits primarily ductile fracture, whereas 304L shows pronounced intergranular stress corrosion cracking (IGSCC), resulting in reduced ductility. Although hydrogen water chemistry suppresses IGSCC in both materials, cracking persists in 304L under methanol-containing aqueous environments. Overall, XM-19 demonstrates superior SCC resistance even after sensitization, highlighting its suitability for structural applications in SMBWR systems.


Keywords

Light-Water Small Modular ReactorAustenitic Stainless SteelSlow Strain Rate Tensile Tests Corrosion Mitigation

Contact Information

葉宗洸
tkyeh@mx.nthu.edu.tw