Investigating and Modeling the Fracture Toughness and Corrosion Properties of Duplex Stainless Steel Welds

Duplex stainless steel (DSS) is crucial in energy operations due to its resistance to chloride‐induced stress corrosion cracking and its superior toughness. The fracture toughness and corrosion properties of the welds are analyzed through empirical welding tests, which include chemical, tensile, microhardness, Charpy impact toughness (CVN), optical microscopy, ferrite, and corrosion resistance. This is followed by design of experiment (DOE) factorial regression, mesh plots, and atomistic simulation and modeling. The spectrum of heat inputs is recognized as the essential factor. The welds exhibit optimal mechanical and corrosion characteristics, evidenced by important metrics including a minimum impact toughness of 122 J at −50°C, a CVN‐derived KIC fracture toughness with a mean value of 128.91 MPa√m, a minimum pitting resistance equivalent number (PREN) of 40.6%, and ferrite content ranging from 38% to 58%. The welding experiment is corroborated by atomistic simulation and modeling of α‐iron body‐centered cubic (BCC) and γ‐iron face‐centered cubic (FCC), resulting in a value of 123 MPa√m at a phase fraction of 50/50. This study determined that atomistic KIC fracture toughness is reliable for design and is significantly correlated with the corrosion parameters of the welds.