I. Concept
Q355GNH weathering steel (also known as atmospheric corrosion-resistant steel) is a low-alloy steel grade between ordinary steel and stainless steel. By adding small amounts of corrosion-resistant elements (e.g., Cu, Ni), it retains the excellent properties of high-quality steel-including strength, ductility, formability, weldability, cuttability, wear resistance, high-temperature resistance, and fatigue resistance-while significantly enhancing weather resistance and corrosion resistance.
II. Chemical Composition (Mass Fraction, %)
| Element | Content Range |
|---|---|
| Carbon (C) | ≤0.12 |
| Silicon (Si) | 0.20~0.75 |
| Manganese (Mn) | ≤1.00 |
| Phosphorus (P) | 0.07~0.15 |
| Sulfur (S) | ≤0.020 |
| Copper (Cu) | 0.25~0.55 |
| Chromium (Cr) | 0.30~1.25 |
| Nickel (Ni) | ≤0.65 |
| Molybdenum (Mo) | ≤0.30 |
| Titanium (Ti) | ≤0.10 |
| Vanadium (V) | ≤0.12 |
| Niobium (Nb) | 0.015~0.060 |
III. Mechanical Properties
| Property | Specification |
|---|---|
| Yield Strength (σs) | ≥355 MPa |
| Tensile Strength (σb) | 490~630 MPa |
| Elongation after Fracture (A50) | ≥26% |
IV. Key Characteristics
High Strength: Boasts high yield and tensile strength, meeting the requirements of various engineering structures.
Excellent Corrosion Resistance: A natural rust layer (surface patina) effectively resists corrosion from moisture, oxygen, and chemicals in the atmosphere, significantly improving structural durability.
Good Weldability: Easy to weld with stable and reliable joint quality.
Environmental Friendliness: Uses eco-friendly coatings during production, reducing environmental pollution.
Aesthetic Appeal: Features a uniform surface patina with an attractive color, offering good decorative effects (for specially treated steel plates).
V. Application Scope
Q355GNH is widely favored for its unique properties, with applications including:
Bridge Engineering: Used as the main structural material for bridges, resisting wind and rain erosion to extend service life.
Construction Engineering: Applied in roofs, walls, and floors to enhance building durability and safety.
Vehicle Manufacturing: Improves corrosion resistance in automobiles, trains, and other vehicles.
Container Manufacturing: Combines good rust resistance and high strength to ensure safe transportation.
Other Fields: Petrochemical, power, and environmental protection industries; railway vehicles, port buildings, oil platforms; and structural parts for chemical/petroleum equipment (e.g., containers for hydrogen sulfide-corrosive media).
Company profile
Founded in 2008, Gnee (Tianjin) Supply Chain Group Co., Ltd. specializes in the global trade and processing of Corten steel products.
We handle all kinds of Corten engineering projects, such as bridges, gardens, hotels, and facade systems.
Compliant with ASTM, EN, and other international standards; third-party inspection supported.
Exported to over 200 countries and regions worldwide.
8 subsidiaries across China and overseas, ensuring global service coverage.
Application Fields: Architecture, landscaping, gardening, cladding, and urban infrastructure.
