1. Key Mechanical Properties
| Property | Value (Metric) | Value (Imperial) |
|---|---|---|
| Yield Strength (ReH) | ≥345 MPa | ≥50 ksi |
| Tensile Strength (Rm) | 490–690 MPa | 71–100 ksi |
| Elongation (A₅) | ≥22% | ≥22% |
| Impact Toughness (KV) | ≥27 J at -20°C | ≥20 ft-lb at -4°F |
Notes:
Comparable to Corten B (ASTM A588) and S355J2WP (EN 10025-5).
Higher manganese (Mn) content improves strength and hardenability.
2. Chemical Composition
| Element | Composition (%) | Role in Weathering Resistance |
|---|---|---|
| C | ≤0.15 | Balances strength & weldability |
| Mn | 0.80–1.50 | Enhances hardenability & toughness |
| Si | 0.15–0.40 | Improves oxidation resistance |
| P | ≤0.035 | Minimizes brittleness |
| S | ≤0.035 | Reduces hot-shortness |
| Cu | 0.20–0.50 | Forms protective patina |
| Cr | 0.30–0.65 | Increases corrosion resistance |
Key Alloying Effects:
Cu + Cr → Stabilizes rust layer, preventing deep corrosion.
Mn + Si → Improves strength without sacrificing weldability.
3. Corrosion Resistance & Environmental Performance
Patina Formation
Develops a dense, adherent rust layer after 1–3 years of exposure.
Protection Mechanism: The patina acts as a barrier, reducing further corrosion (typical rate: 0.002–0.005 mm/year in rural/urban areas).
4. Fabrication & Welding Guidelines
Machining & Cutting
Plasma/Laser Cutting: Preferred for clean edges.
Oxyfuel Cutting: Possible but may require post-cut grinding.
Welding Recommendations
Preheat: 100–150°C (for thickness >20mm).
Electrodes: Use low-hydrogen rods (e.g., AWS E7018-W2).
Post-Weld: Avoid grinding; let patina form naturally.
5. Typical Applications
✔ Bridges & highway structures
✔ Transmission towers
✔ Architectural facades & sculptures
✔ Railway wagons & shipping containers
