Superduplex Pitting Resistance Factor
The super duplex pitting resistance factor quantifies the pitting resistance of high-alloy duplex microstructures in chloride-rich environments. It accounts for the combined effects of alloying elements.
Physicochemical Mechanism of Action
The Super Duplex Pitting Resistance Factor (SDPRF) measures how well duplex steel resists pitting in chloride-rich environments. This factor takes into account the chemical composition of the steel and how the various elements work together to reduce the attack potential.
Metallurgical Relevance & Welding Risks
A low SDPRF value means the steel is more prone to pitting. This can lead to corrosion and possibly cracks. If handled incorrectly or if materials with insufficient corrosion resistance are used, the service life of the component can be drastically reduced.
Shop Practice & Action Items
To increase the SDPRF value and minimize pitting risk, the following measures should be taken:
• Use highly alloyed duplex steels with high nickel and molybdenum content.
• Ensure the weld cools properly to get a homogeneous structure.
• Avoid excessive carbon pickup, as this can increase the attack potential.
• Regularly test the material's corrosion resistance in the specific environment.