420MPa Yield S420K2W Weathering Steel Plate, K2 Grade is a high-strength structural steel compliant with EN 10025-5, engineered for demanding outdoor applications that require a balance of mechanical robustness and corrosion resilience. The "S420" in the grade denotes a minimum yield strength of 420 MPa, ensuring reliable load-bearing capacity for heavy-duty structures, while "K2 Grade" specifies impact resistance of ≥27J at -20℃, critical for maintaining toughness in cold environments. The "W" signifies weathering capability, achieved through alloying elements like copper, phosphorus, and chromium that form a dense, protective rust layer-reducing corrosion rates by 2–5 times compared to unalloyed steels and eliminating the need for frequent protective coatings.
Mechanically, this steel offers a tensile strength range of 520–680 MPa and an elongation rate of ≥21%, balancing high strength with formability for ease of fabrication and welding (surface preparation to remove loose rust is recommended for optimal weld quality). Its self-protective rust layer stabilizes over time, creating a natural barrier against atmospheric moisture, pollutants, and temperature fluctuations, making it ideal for long-term use in exposed structures such as bridges, transmission towers, railway wagons, and industrial equipment in coastal, urban, or industrial zones.
While initial exposure may result in minor rust runoff as the protective layer develops, this is a temporary phase that gives way to a stable, low-maintenance surface. Compared to standard structural steels, S420K2W reduces lifecycle costs by minimizing painting and repair needs, aligning with sustainable construction practices. Always confirm compliance with EN 10025-5:2004 and delivery conditions (e.g., hot-rolled) to meet project specifications. This steel embodies a combination of technical excellence-high strength, impact resistance, and weathering durability-making it a trusted choice for critical infrastructure where reliability and cost-efficiency are paramount.
FAQ
Q: What does "K2 Grade" mean for this steel?
A: K2 Grade means the steel has ≥27J impact resistance at -20℃, suitable for cold-climate applications.
Q: How strong is this steel?
A: It has a minimum yield strength of 420 MPa, ideal for high-load structural projects.
Q: Why is "W" important in S420K2W?
A: "W" indicates weathering resistance-alloy elements form a protective rust layer to reduce corrosion in outdoor environments.
Q: Where is this steel commonly used?
A: Used for bridges, towers, railway cars, and industrial structures in corrosive or exposed outdoor settings.
Q: Do I need to paint S420K2W?
A: No-its weathering property allows natural rust protection, though initial rust may run off before the layer stabilizes.
