S355J5W Weathering Steel Plate -50℃ Impact Resistant is a premium structural steel grade under the European standard EN 10025-5, engineered for demanding outdoor applications where high strength, impact toughness, and corrosion resistance are critical. The designation "S355" indicates a minimum yield strength of 355 MPa (for thickness ≤16mm), while "J5" specifies exceptional impact performance at -50℃, ensuring reliable toughness in frigid environments. The "W" denotes its weathering capability, achieved through strategic alloying with elements like copper (Cu), phosphorus (P), chromium (Cr), and nickel (Ni), which form a dense, adherent oxide layer to protect against rust and reduce corrosion rates by 2-8 times compared to conventional steel.
Mechanically, this steel offers a tensile strength range of 490-630 MPa and an elongation rate of ≥21%, balancing robustness with formability. Its -50℃ impact resistance (typically ≥27J in longitudinal tests) makes it suitable for structures subjected to extreme cold, such as northern-region bridges, offshore platforms, or transportation equipment. The weathering property eliminates the need for frequent painting, lowering lifecycle costs while maintaining structural integrity in industrial, coastal, or humid environments.
Common applications include railway carriages, transmission towers, container frameworks, and architectural elements exposed to the elements. While originally standardized under EN 10025-5:2004, users should verify compliance with the latest revisions (e.g., EN 10025-5:2024), as newer grades like S355K2W (-40℃ impact) may serve as alternatives. Supplied in hot-rolled, normalized, or normalized-rolled conditions, S355J5W ensures versatility in fabrication and welding. For global projects, it aligns with equivalent standards like China's Q355NHJ5W and the U.S. A588 Grade K, making it a preferred choice for international engineering teams seeking reliable, low-maintenance structural solutions.
FAQ
Q: What standard does S355J5W follow?
A: EN 10025-5 (weathering structural steel).
Q: At what temperature does S355J5W achieve impact resistance?
A: -50℃ (-58°F), ensuring toughness in cold climates.
Q: How does S355J5W resist corrosion?
A: Alloying elements (Cu, Cr, Ni) form a protective oxide layer to combat atmospheric corrosion.
Q: What are typical uses for this steel?
A: Bridges, towers, containers, and outdoor structures in corrosive environments.
Q: Are there equivalent grades in other standards?
A: Yes, e.g., China's Q355NHJ5W and U.S. A588 Grade K.
