What is Corten A Corten Steel?
Corten A Weathering Steel is the most classic high-phosphorus weathering steel grade, belonging to the ASTM low-alloy high-strength steel system. When Corten A steel plates are exposed to the atmosphere and industrial flue gases, a dense and highly stable oxide layer (patina) naturally forms on the steel surface through self-catalyzed reactions.
This nearly zero-porosity protective film adheres tightly to the base metal like armor, effectively isolating moisture, oxygen, and acidic gases, and preventing corrosion from penetrating inward.
Under fully unpainted and exposed conditions, Corten A can achieve a weathering resistance lifespan of 4 to 8 times that of ordinary carbon steel, with a total service life of 50 to 100 years.
After an initial stabilization period in the early years, ordinary carbon steel continues to corrode and lose thickness at an annual rate of approximately 30 μm, whereas the long-term corrosion rate of Corten A sharply decreases to around 1–2 μm per year, which is only about 1/20 to 1/30 of that of conventional carbon steel.
With the ongoing expansion of industrialization in the Middle East and globally across power generation, petrochemical, and heavy energy industries, the demand for high-strength steels with resistance to high temperatures and atmospheric corrosion continues to grow rapidly.
The unique high-phosphorus design of Corten A, combined with chromium elements, enables it to maintain structural stability even in industrial environments reaching up to 450°C.
Therefore, Corten A is increasingly being used in critical energy and infrastructure projects worldwide, including chimney projects in Iraq, providing steel solutions that combine superior safety performance with exceptional cost efficiency.
Corten A Weathering Steel Plate Specification
| Item | Description |
|---|---|
| Grade | Corten A (ASTM Weathering Steel Grade) |
| Standard | ASTM A242 / ASTM A588 equivalent / EN equivalent |
| Thickness | 2.0 mm – 100.0 mm |
| Width | 1000 mm – 3000 mm |
| Length | 2000 mm – 12000 mm (customized) |
| Surface Finish | Mill finish / Rusted patina (natural weathering) / Shot blasted |
| Processing | Cutting, bending, welding, drilling, CNC machining |
| Delivery Condition | Hot rolled / Normalized / As-rolled |
| Inspection | Chemical composition test, Mechanical properties test, UT, PMI, dimensional inspection |
Corten A weathering steel plates are strictly inspected before shipment to ensure full compliance with ASTM A242 / ASTM A588 and international project requirements.
Chemical composition is verified to ensure proper weathering performance, including key alloying elements such as Cu (0.25–0.55%), Cr (0.30–1.25%), and controlled phosphorus content depending on specification requirements.
Mechanical properties are strictly controlled within standard ranges, typically including a minimum yield strength of ≥345 MPa, tensile strength of 485–620 MPa, and elongation of ≥18–21% depending on thickness.
Ultrasonic testing (UT) is performed at 100% coverage in accordance with ASTM A578 / EN 10160 standards to ensure internal soundness and defect-free quality.
Dimensional tolerances are controlled according to ASTM / EN hot-rolled plate standards, typically within ±0.3–1.5 mm depending on thickness range.
All results are recorded in a Mill Test Certificate (MTC) compliant with EN 10204 3.1 or 3.2, and third-party inspection reports (SGS, BV, TUV) can be provided to ensure full traceability for export projects such as industrial chimneys and infrastructure applications.
We provide full processing services for Corten A weathering steel plates to meet different engineering and architectural needs. Cutting services include laser cutting, plasma cutting, flame cutting, and custom size cutting according to drawings.
We also offer bending and forming services such as hot/cold bending, plate rolling, and edge forming to create curved or customized shapes for structural and design applications.
Welding and fabrication services are available, including MIG, MAG, and TIG welding, as well as assembly of steel components and structural parts for outdoor projects.
Surface treatment options include shot blasting (SA2.5), cleaning, and controlled pre-rusting treatment to achieve a stable weathering patina effect.
We also provide drilling and CNC machining services such as hole drilling, punching, slotting, and precision machining based on project drawings.
In addition, we can supply finished fabricated components and provide technical support, CAD assistance, and export packaging to ensure safe delivery for global projects.
Corten A weathering steel plates are typically packaged using a standard export-ready protection system to ensure safe transportation and prevent moisture damage during shipping.
The steel plates are wrapped with waterproof plastic film to protect against rain, humidity, and salt spray corrosion during ocean transport. In some cases, kraft paper may be added as an additional surface protection layer to prevent scratches and minor surface damage.
All plates are securely bundled with steel straps to maintain stability during handling and loading. Depending on order size and customer requirements, the steel plates are packed on wooden pallets or in wooden crates, or directly loaded into containers with internal reinforcement for heavy-duty shipments.
This packaging method ensures that Corten A steel plates remain well-protected during long-distance international transportation and arrive in stable condition for further processing or direct use.
We offer multiple shipping options for Corten A steel plates, including direct routes to major Iraqi ports such as Umm Qasr. The typical transit time from China to Iraq is approximately 25 to 35 days, depending on the shipping schedule.
We closely monitor local import regulations, including customs duties, VAT policies, and any relevant steel import requirements, ensuring smooth clearance for all shipments.
All export documents are fully prepared, including commercial invoices, packing lists, bill of lading, and certificate of origin. Third-party inspection certificates can also be provided when required.
If you are sourcing for your Iraq project, feel free to contact us for a quotation or shipping consultation. We are ready to support your procurement with reliable supply and logistics solutions.
