Description: BBN steel is a well-known steel manufacturer and service provider in China, Corten A Weather Resistant Steel is our superior product, we are favored by customers with high quality, competitive price and excellent service
Payment Terms: L/C, T/T, D/P, Western Union, Paypal, Money Gram
ASTM Corten A Weather Resistant Steel Plate | Hot Rolled Weathering Structural Steel, 345 MPa Min Yield, No Painting Required
ASTM Corten A | Hot Rolled Weathering Structural Steel Plate | Yield 345 MPa Min, Tensile 485 MPa, Elongation 20% Min, Bend 1t | Thickness 6–420 mm, Width 100–4200 mm, Length 100–4200 mm | Self-Protecting Rust Patina for Facades, Bridges, Gas Flues & Outdoor Structures
Self-Protecting Patina, No CoatingCopper, chromium, nickel and phosphorus drive the surface to a dense adherent oxide layer that blocks further corrosion — no paint system and no repainting cycle.
345 MPa Min Yield, 485 MPa TensileStructural strength with 20% minimum elongation and a 1t bend parameter, so facade and bridge plate can be loaded and formed.
Full Size Programme, Cut to DrawingThickness 6–420 mm with width and length up to 4200 mm; stock despatched in 3–7 days, custom processing in 15–30 days.
01Product Overview
ASTM Corten A is a widely used atmospheric corrosion-resistant weathering steel. It is alloyed with copper, chromium, nickel and phosphorus, which gives it superior anti-corrosion performance and a unique surface texture. It is the grade of choice for gas flue systems and aesthetic building facade applications.
What sets Corten A apart from an ordinary carbon steel plate is what happens once it is put into service. Left exposed to the atmosphere, it forms a dense, self-protecting rust patina that stops further corrosion — so unlike regular carbon steel it needs no paint and no coating, and the structural service life is greatly extended. First adopted for construction in 1958, Corten A is now specified worldwide for bridges, railways, vehicles and outdoor industrial structures.
345 MPaYield Strength (Min)Corten A
485 MPaTensile StrengthCorten A
20 %Elongation (Min)Corten A
4–8×Service Life vs Plain Carbon SteelNo anti-corrosion coating
02Technical Specifications
We stock full-size hot-rolled Corten A steel plates with complete standard compliance, and custom cutting, bending and forming is available to meet architectural and structural project requirements.
Shot blasting, painting or coating available on request — confirm whether the plate is to weather naturally or be coated Mill FinishShot BlastedPainted or Coated
Surface Condition
Smooth surface, uniform texture, no cracks, no lamination
Core Advantage
Self-protecting weather resistance, no coating required, aesthetic rust surface, high structural strength
Main Application
Building facade, bridge structure, gas flue system, railway & vehicle equipment, outdoor industrial structure
MOQ
1 Ton / Negotiable
Delivery Time
3–7 days (stock); 15–30 days (custom processing)
Certification
MTC / EN 10204 3.1 / Third-party inspection supported
Custom Service
Custom size cutting, bending, forming, surface treatment and deep processing
Payment Terms
T/T, L/C, Western Union, Trade Assurance
Note: The thickness, width and length above are the mill programme for Corten A — not every combination inside those limits rolls in every thickness. Send us your required thickness, width, length, quantity and whether the plate is to weather naturally or be coated, and we will confirm stock status, the exact lead time and the certificate package against the item before you order.
03Equivalent Grades
Corten A matches multiple global standard grades. The table below lists the equivalent materials for quick engineering replacement and international procurement.
Standard System
Equivalent Grade
ASTM Standard
A242 Type 1A588 Grade A
European EN Standard
Fe510A1K1DD2K1 (EN 10155)
French NFA Standard
E36W (NFA35-502)
German SEW Standard
S.E.W 087
Note: Equivalent grades differ slightly in chemical composition and in the mechanical limits each standard sets, so they are not automatically interchangeable. Verify the composition range, the thickness limits and the inspection requirements against your design code before substituting one for another. Tell us which standard your drawings call up and we will supply the plate with the matching certificate.
04Chemical Composition
Corten A is a low-alloy weathering steel formulated with precise copper, chromium, nickel and phosphorus content. This optimised composition delivers stable atmospheric corrosion resistance and reliable structural performance for long-term outdoor service.
Grade
C (Max)
Si
Mn
S (Max)
Cr
Ni
Cu
Nb
Nb+V+Ti
P
Corten A
0.12
0.25–0.75
0.20–0.50
0.07–0.15
0.50–1.25
0.65
0.25–0.55
0.25–0.55
—
0.07–0.15
Note: The figures above are reproduced from the Corten A data sheet supplied with this page. Phosphorus at 0.07–0.15% is the characteristic Corten A range and, together with copper 0.25–0.55%, chromium 0.50–1.25% and nickel up to 0.65%, is what builds the protective patina — carbon is held to 0.12% max to keep the plate weldable. The data sheet does not set a value for Nb+V+Ti, so that cell is left blank rather than filled with a number the source does not support. Where a project sets its own limits for sulphur or micro-alloying elements, the applicable figures are confirmed on the mill certificate.
05Weathering Performance & Patina Formation
The patina is not a defect — it is the protection system. Understanding how it develops is what decides whether a weathering grade is right for your structure.
1
Initial Exposure
Freshly descaled plate begins to oxidise on site. Runoff staining of adjacent concrete, stone or cladding is normal during this first phase.
2
Wet & Dry Cycling
Alternating wetting and drying drives the copper, chromium, nickel and phosphorus into a dense, tightly bonded oxide layer.
3
Patina Densification
The layer becomes adherent and non-porous, cutting off the transport of oxygen and moisture to the base steel underneath.
4
Stabilised Protection
The corrosion rate falls away and the plate is protected for its service life with no paint and no coating — the reason Corten A is quoted at 4–8 times the service life of ordinary carbon steel.
Note: The patina only stabilises under alternating wet and dry conditions. In continuously humid or shaded locations, in marine salt-spray exposure, in buried or immersed service, or where de-icing salt runoff collects, the layer does not stabilise and a coating system is required instead. Design drainage so the plate can dry out, and detail the surrounding materials for initial runoff staining. Tell us the exposure condition and we will confirm whether a bare weathering grade is the right call for your project.
06Mechanical Properties
Corten A offers high strength, stable tensile properties and good ductility. It resists deformation under long-term outdoor exposure and meets the structural safety requirements of buildings, bridges and industrial facilities.
Grade
Permissible Yield Point Ratio
Yield Strength (MPa, Min)
Tensile Strength (MPa)
Elongation (%, Min)
Bend Parameter
Corten A
—
345
485
20
1t
Note: The source data sheet does not set a value for the permissible yield point ratio, so that cell is left blank rather than filled in. The 1t bend parameter means the plate can be bent around a mandrel of one times its thickness. The values above are the room-temperature figures for the as-supplied plate; if material is hot formed, normalised or supplied in a heavier thickness than the tested range, confirm the mechanical values from the mill certificate for your specific item.
07Processing & Fabrication Parameters
Corten A features excellent machinability. All common processing methods are applicable, with the standardised parameters shown below.
Processing Item
Technical Parameters & Operation Notes
Hot Forming
Standard temperature range 800 °C – 1050 °C. Normalizing treatment is recommended if a non-standard forming temperature is adopted, to keep the mechanical performance stable.
Flame Cutting
Conventional flame cutting methods apply and no preheating is required. Do not cut plate whose surface temperature is below 10 °C, to avoid brittleness and cutting defects.
Drawing & Forming
Balanced strength and ductility support moderate cold drawing and bend forming for customised structural shapes.
Welding Performance
Applicable processes: spot welding, TIG, MIG, MAG and electrode welding. No cold cracking risk; control the welding linear energy ratio to avoid softening of the heat-affected zone. Post-weld stress relief is generally unnecessary.
Note: These are the shop parameters we work to for Corten A. The 10 °C minimum surface temperature before flame cutting is the one that is most often missed on winter site work — cold plate is the usual cause of cut-edge cracking. Where a weld procedure qualification is required, we supply the heat analysis so your Pcm and Ceq can be calculated from the actual plate rather than from a typical value.
08Applications & Typical Uses
From architectural cladding to high-temperature flue systems, Corten A is chosen wherever long outdoor life and a controlled rust appearance are both required.
Architectural Decoration
Building exterior facades, curtain wall, landscape art structures and retro architectural decoration projects.
Infrastructure Engineering
Urban bridges, viaducts, outdoor structural supports and municipal corrosion-resistant facilities.
Industrial Systems
Gas flue pipelines, high-temperature flue treatment systems and industrial anti-corrosion piping.
Transportation Equipment
Railway trains, trucks, containers and corrosion-resistant vehicle structural parts.
Outdoor Industrial Facilities
Outdoor storage tanks, industrial equipment supports and steel structures in long-term atmospheric exposure.
09Core Advantages
Five reasons specifiers keep coming back to Corten A for outdoor and architectural work.
1
Superior Weather Resistance
Forms a dense self-protective rust patina that blocks further corrosion — 4–8 times longer service life than ordinary carbon steel without any anti-corrosion coating.
2
High Structural Performance
Stable yield and tensile strength with good ductility and deformation resistance, meeting the long-term load-bearing requirements of outdoor structures.
3
Excellent Processability
Supports hot forming, cold bending, flame cutting and all conventional welding processes, with low processing difficulty.
4
Aesthetic Surface Effect
A unique retro rust surface texture that combines structural durability with architectural decorative value.
5
Cost-Effective
No regular painting maintenance is required, which greatly reduces the long-term operation and maintenance cost of the steel structure.
We supply high-quality ASTM Corten A weathering steel plates with full specifications, complete certification and strict factory inspection. We provide one-stop custom fabrication including cutting, bending, forming and surface treatment, plus deep processing to your drawings. All products are delivered with MTC / EN 10204 3.1 documentation and third-party inspection is supported. Contact us for technical support and competitive wholesale pricing!
10Frequently Asked Questions
Short answers to the questions we are asked most often about ASTM Corten A. For anything not covered here, send us your drawings and specification.
Q1What is Corten A, and how is it different from ordinary carbon steel?
Corten A is an atmospheric corrosion-resistant weathering steel alloyed with copper, chromium, nickel and phosphorus. Left exposed to the weather it forms a dense, self-protecting rust patina that stops further corrosion, so unlike regular carbon steel it needs no paint or coating and delivers 4–8 times the service life. It also carries 345 MPa minimum yield and 485 MPa tensile strength, so it is a structural plate, not just a cladding material.
Q2Does Corten A really need no painting at all?
It needs no painting when it can dry out. The patina only stabilises under alternating wet and dry conditions. In continuously humid or shaded locations, in marine salt-spray exposure, where de-icing salt runoff collects, or in buried and immersed service, the layer does not stabilise and a coating system should be specified instead. Design the detail so water drains and the plate can dry, and allow for runoff staining of adjacent concrete or stone during the initial weathering period. Tell us the exposure and we will tell you honestly whether a bare weathering grade suits the job.
Q3Which grades are equivalent to Corten A?
Corten A matches ASTM A242 Type 1 and ASTM A588 Grade A, Fe510A1K1 / DD2K1 under EN 10155, E36W under NFA35-502 and S.E.W 087 under the German SEW standard. They differ slightly in composition and in the mechanical limits each standard sets, so verify against your design code before substituting. If your project is specified directly to EN 10155, we also supply S355J2WP weathering plate — tell us which standard your drawings call up and we will match it.
Q4What are the mechanical properties and what sizes can you supply?
Corten A is supplied at 345 MPa minimum yield, 485 MPa tensile strength, 20% minimum elongation and a 1t bend parameter. The size programme is thickness 6–420 mm with width and length up to 4200 mm. Not every width and length combination rolls at every thickness, so send us the three dimensions and the quantity and we will confirm what is actually available.
Q5How is Corten A cut, formed and welded?
Hot forming is done at 800–1050 °C, with normalizing recommended if a non-standard temperature is used. Flame cutting needs no preheating, but do not cut plate below 10 °C surface temperature — that is the usual cause of cut-edge cracking on winter site work. Moderate cold drawing and bend forming are supported. Spot, TIG, MIG, MAG and electrode welding are all applicable with no cold cracking risk; control the welding linear energy ratio to avoid softening the heat-affected zone, and post-weld stress relief is generally unnecessary.
Q6What are your MOQ, lead time, certification and custom services?
MOQ is 1 ton / negotiable. Lead time is 3–7 days for stock and 15–30 days for custom processing. Certification is MTC / EN 10204 3.1 with third-party inspection supported. Custom services cover size cutting, bending, forming, surface treatment and deep processing to your drawings, with shot blasting, painting or coating where the plate is not intended to weather bare. Payment is by T/T, L/C, Western Union or Trade Assurance.
Get Your ASTM Corten A Weather Resistant Steel Plate Quotation
Send us your plate dimensions (thickness / width / length), quantity, surface treatment and certification requirement. We will reply with the latest stock status, competitive wholesale price and complete certification documents within 24 hours.
BBN Steel has established a complete set of production and supplier management system processes to ensure the improvement of product quality and better service to users.
Production Control
BBN Steel has established a complete production quality control process to ensure every link from research and development to mass production.
Supplier management
Our supplier selection will consider factors such as health and safety, ethics, environmental protection, price and quality to better serve customers.
Certification & Patent
We have successively won various international authoritative certifications, GB /T19001-ISO9001: 2000 quality management system was implemented.
After sales service
We provide booking space, shipping tracking service and after-sales service, we will always be first-class products and perfect pre-sale and after-sales service.
Get in Touch
Welcome to contact us through online consulting, emails and hotline if you are interested in our company or products. Our staff will reply you within 24 hours.
Address: HIGH-TECH DEVELOPMENT ZONE, ZHENGZHOU, CHINA
