High-strength weathering steel plate and sheet designed for long-term outdoor and structural use. Q355GNH is a low-alloy structural steel formulated to form a stable, protective rust layer (patina) that slows further corrosion in many atmospheric environments. It combines improved atmospheric corrosion resistance with the mechanical properties and fabricability required for heavy structural applications.
Key features
- Weathering (atmospheric-corrosion-resistant) low-alloy steel with enhanced surface patina formation
- Suitable for heavy structural applications: bridges, towers, railway and road vehicles, building structures, and other outdoor steelwork
- Available product forms: plates, sheets, coils and sections
- Good weldability, formability and strength for structural fabrication
Standard dimensions & ordering
- Width: 1,220 mm to 4,200 mm
- Length: 5,000 mm to 18,000 mm (coils available for thickness ≤ 25 mm)
- Minimum order quantity: 10 pieces
- Delivery: stock items shipped promptly; production lead time typically 10–40 days
- Payment: T/T or L/C at sight
- Mill Test Certificate (MTC) available
Heat treatment, testing & surface options
- Production/process options: TMCP (Thermo-Mechanical Controlled Processing), Normalized (N), Quenched & Tempered (Q+T)
- Thickness-direction tests: Z15, Z25, Z35
- Impact testing: Charpy V-notch
- Non-destructive testing: UT (ultrasonic), HIC, NDT, PWHT simulation (where required)
- Coating and surface preparation options: shot blasting, coating (per customer specification)
- Compliance/testing on request: NACE0175, third-party inspection (e.g., SGS)
Why specify Q355GNH
- Offers a cost-effective alternative to stainless steel where full stainless corrosion resistance is not required
- Lower alloy content than stainless grades keeps material and fabrication costs down while delivering adequate atmospheric corrosion resistance for many infrastructure and outdoor structural uses
Ordering notes
For quotations, specify required dimensions (thickness, width, length), quantity, required certification/tests, surface finish or coating, and desired delivery timeframe. Lead times and pricing vary by thickness, quantity and testing requirements.
Product Details
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