Origin of Weathering Steel
Corten is a trademark originally created by U.S. Steel in the 1930s.
The name itself comes from two key performance characteristics:
| Name Component | Meaning | Performance Benefit |
|---|---|---|
| COR | Corrosion Resistance | Forms a stable rust-like patina that protects the steel |
| TEN | Tensile Strength | Provides high structural strength for load-bearing use |
The main innovation was that the rust layer was engineered to become a protective barrier, not a weakness.
This eliminated the need for painting, reducing fabrication and life-cycle maintenance costs.
Originally developed for coal railroad hopper cars, Corten quickly became a staple in bridge construction, building façades, and large-scale public architecture.
Weathering Steel Grade Specifications
| Standard | Product Forms | Typical Yield Strength (min.) | Typical Tensile Strength (min.) | Thickness Range | Main Use Cases |
|---|---|---|---|---|---|
| ASTM A242 | Plate / Sheet | 50 ksi (345 MPa) | 70 ksi (485 MPa) | Up to 19mm | Architectural cladding, bridges |
| ASTM A588 | Plate / Structural Sections | 50 ksi (≤100mm) | 70 ksi | Up to 100mm | Structural beams, support elements |
| ASTM A606-4 | Cold-rolled sheet / coil | 50 ksi | 70 ksi | Thin gauge materials | Roofing & perforated wall panels |
| ASTM A847 | Tubing / Pipe | 50 ksi | 70 ksi | Varies | Handrails, screens, structural tubing |
For perforated panels, ASTM A606-4 is among the most commonly specified due to easy forming and uniform surface patina.
Pros and Cons of Using Perforated Corten Steel
Advantages
| Benefit | Description | Practical Impact |
|---|---|---|
| High Longevity & Strength | Meets 50 ksi minimum yield strength | Suitable for structural & façade applications |
| Self-Healing Patina | Rust layer stabilizes & protects steel | No paint or coating required |
| Distinct Architectural Appearance | Warm, earthy rust tones blend with natural or urban environments | Used in urban plazas, museums, civic buildings |
| Reduced Maintenance Costs | No repainting or coating lifecycle required | Up to 60–90% lower maintenance over lifespan |
Disadvantages
| Limitation | Explanation | Recommendation |
|---|---|---|
| Higher Initial Material Cost | Higher alloy content & lower production volume | Cost offsets over long service life |
| Not Suitable for All Climates | Patina fails in constant humidity or salt spray | Avoid coastal, rainforest, marine exterior zones unless sealed |
| Rust Runoff Staining | Patina can bleed onto stone, concrete, or light surfaces | Use drip edges, stand-off panels, or drainage planning |
Common Applications of Perforated Corten Steel
Architecture & Buildings
Exterior façades and rainscreens
Decorative perforated cladding
Roofing and screen walls
Example: Barclays Center, Brooklyn, USA
Sculpture & Public Art
Outdoor monuments and public installations
Example: Chicago Picasso Sculpture
Landscape & Urban Design
Planter boxes, retaining walls, pedestrian screen fencing
Garden edging and walkway partitions
Perforation Options and Processing Capabilities
We supply perforated Corten Steel in multiple forms:
| Supply Form | Gauge Range | Maximum Width | Notes |
|---|---|---|---|
| Sheets / Blanks | 24 gauge (0.6mm) → 1/2" (12.7mm) | Up to 1500mm (60") | Most common for façade panels |
| Coils | Thin-gauge | Standard coil widths | Ideal for continuous production |
| Flat Panels | Laser or plasma cut | Custom sizes up to 12m length | Large-format architectural panels |
Available Perforation Patterns
Round, Square, Slotted, Hexagonal
Custom logo, image, gradient, and parametric patterns available
Perforation open area: 5% → 60% depending on shading, airflow, or privacy needs
Perforated Corten Steel offers a powerful combination of:
Durability
Low Maintenance
Architectural Warmth
Structural Performance
When applied in the right environment with good drainage design, it can last 40–80+ years while maintaining an evolving visual character that becomes richer over time.
