Corten Steel Plates Supplier

Corten A & Corten B Weathering Steel Plates and Sheets

Dinesh Tube India supplies Corten steel plates and sheets from Mumbai to fabricators, railway wagon builders, structural contractors, chimney and duct makers, architects and signage firms across India and abroad. We supply Corten A (ASTM A242 type) and Corten B (ASTM A588 type), the European weathering grades S355J0W, S355J2W, S355K2W and S355J0WP, and Indian Railways IRSM 41-97 plates, in full mill sizes or cut to size, with mill test certificates.

Corten is a weathering steel: a low-alloy steel with copper, chromium, nickel and phosphorus that forms a tight, protective rust layer (patina) in the open air. It is not stainless steel and it does still rust; the patina slows further atmospheric corrosion so the steel can often be left unpainted. Corten pipes and tubes are on our Corten steel pipes and tubes page.

Table of Contents

What Is Corten Steel?
Corten A vs Corten B
Specification & Sizes
Chemical Composition
Mechanical Properties
Corten Plate Grades We Supply
Applications & Where Not to Use
HSN Code
FAQs

What Is Corten Steel?

Corten (COR-TEN, from "corrosion resistance" and "tensile strength") began as a trade name for weathering steel. Today "Corten plate" is used for any weathering steel plate made to ASTM A242, ASTM A588, EN 10025-5, JIS G3114 / G3125 or IRSM 41-97. Small additions of copper, chromium, nickel and phosphorus make the rust layer dense and adherent instead of flaking, so after repeated wet and dry cycles the corrosion rate drops well below that of plain carbon steel.

The patina usually takes from several months to a few years to stabilise, depending on climate, rain exposure and how often the surface dries out. Until then, run-off can stain concrete or paving below, which architects allow for with drip details and drainage.

Corten weathering steel plates in stock at Dinesh Tube India, Mumbai

Corten A vs Corten B

Point	Corten A	Corten B
Closest ASTM / ASME grade	ASTM A242 Type 1 / ASME SA242	ASTM A588 Gr A / ASME SA588
Closest EN 10025-5 grade	S355J0WP / S355J2WP	S355J0W / S355J2W / S355K2W
Closest JIS grade	SPA-H (JIS G3125)	SMA 490 (JIS G3114)
Key chemistry	High phosphorus (about 0.07–0.15%), Cu, Cr, Ni	Low phosphorus, Cu, Cr plus vanadium
Typical thickness	Thinner plates and sheets	Medium and heavy structural plates
Weldability	Good in thin sections; phosphorus limits heavy welding	Better for thick, heavily welded structures
Typical use	Cladding, facades, signage, containers, chimneys, wagons	Bridges, towers, heavy structures, large fabrications

Corten A and Corten B are trade descriptions, not standards. Always order to a standard and grade (for example "ASTM A588 Gr A" or "EN 10025-5 S355J2W") so the mill certificate can be checked against it.

Chemical Composition of Corten Steel Plates (%)

Grade	C	Si	Mn	P	S	Cu	Cr	Ni	V
Corten A (typical)	0.12 max	0.25–0.75	0.20–0.50	0.07–0.15	0.030 max	0.25–0.55	0.50–1.25	0.65 max	–
Corten B (typical)	0.16 max	0.30–0.50	0.80–1.25	0.030 max	0.030 max	0.25–0.40	0.40–0.65	0.40 max	0.02–0.10
ASTM A588 Gr A	0.19 max	0.30–0.65	0.80–1.25	0.04 max	0.05 max	0.25–0.40	0.40–0.65	0.40 max	0.02–0.10
ASTM A242 Type 1	0.15 max	–	1.00 max	0.15 max	0.05 max	0.20 min	–	–	–
EN S355J2W	0.16 max	0.50 max	0.50–1.50	0.030 max	0.030 max	0.25–0.55	0.40–0.80	0.65 max	–
EN S355J0WP	0.12 max	0.75 max	1.00 max	0.06–0.15	0.035 max	0.25–0.55	0.30–1.25	0.65 max	–

Heat (ladle) analysis. "Typical" rows for Corten A and B follow published producer data; the governing limits are those of the ordered standard and the mill test certificate. EN grades may also contain Mo and Zr within the standard's limits.

Mechanical Properties of Corten Steel Plates

Grade / Thickness	Yield Strength (min)	Tensile Strength	Elongation (min)	Impact
ASTM A242 / Corten A, up to 19 mm	345 MPa	485 MPa min	21% (50 mm)	On request
ASTM A588 / Corten B, up to 100 mm	345 MPa	485 MPa min	21% (50 mm)	On request
ASTM A588, over 100 to 125 mm	315 MPa	460 MPa min	21% (50 mm)	On request
EN S355J0W / J0WP, up to 16 mm	355 MPa	470–630 MPa	22%	27 J at 0 °C
EN S355J2W, up to 16 mm	355 MPa	470–630 MPa	22%	27 J at −20 °C
EN S355K2W, up to 16 mm	355 MPa	470–630 MPa	22%	40 J at −20 °C
IRSM 41-97	340 MPa	480 MPa min	21%	–

Yield strength falls with thickness under every standard; check the table in the standard for your plate thickness.

Corten Plate Grades We Supply

ASTM A588 Gr A Plates

Corten B type structural weathering plate for bridges, towers and heavy fabrication.

A588 Gr A plates

ASTM A242 Type 1 Plates

Corten A type high-phosphorus weathering plate for thinner sections and cladding.

A242 Type 1 plates

S355J2W Plates

EN 10025-5 weathering steel with 27 J impact at −20 °C; also S355K2W (old S355K2G1W).

S355J2W plates · S355K2G1W · S355J2G1W

S355J0WP Plates

High-phosphorus EN equivalent of Corten A for sheets and thinner plates.

S355J0WP plates

IRSM 41-97 Plates & Sheets

Indian Railways corrosion-resistant steel for wagon and coach bodies, roofs and underframes.

Corten Signage & Name Boards

Corten sheets cut and shaped for name boards, signage, facades and planters.

Corten steel signages

Corten Steel Plate Applications

Railway wagons and coaches (IRSM 41-97)
Bridges and structural steelwork
Transmission and telecom towers
Chimneys, stacks and flue gas ducts
Air preheater casings and ducting
Shipping containers, truck and trailer bodies
Facades, cladding and roofing
Signage, name boards, planters and landscape edging
Sculptures and public art

Industries and architectural uses for Corten weathering steel plates

For Corten tubes in air preheaters, see air preheater tubes. For wear-resistant plate, see AR plates.

Where Corten Is Not a Good Choice

Coastal splash zones and marine immersion, where chlorides stop a stable patina forming
Surfaces that stay wet, are buried in soil or are covered by debris or vegetation
Chemical, food or pharmaceutical process contact; use stainless steel plates instead
Areas exposed to de-icing salt or heavy industrial chemical fumes

Corten Steel HSN Code

Corten plates and sheets fall under HSN Chapter 72 (flat-rolled steel). The exact 8-digit code depends on thickness, width, whether the material is in coils, and whether its Cr, Cu or Ni content makes it "alloy steel" under the Chapter 72 notes (heading 7225) or non-alloy (heading 7208). We state the HSN code on every invoice; confirm the code for your import with your customs broker.

Need Corten plates or sheets? Send the standard and grade, thickness, plate size or cut sizes, quantity and delivery location to kamlesh@dineshtube-india.com or call +91 83559 10913. You can also send an enquiry.

Corten Steel Plates: FAQs

What is the difference between Corten A and Corten B?

Corten A is a high-phosphorus weathering steel (about 0.07–0.15% P) close to ASTM A242 and EN S355J0WP, used mainly for thinner plates and sheets in cladding, signage, containers and chimneys. Corten B has low phosphorus with added vanadium, is close to ASTM A588 Gr A and EN S355J2W, and is preferred for thicker, heavily welded structures such as bridges and towers.

Is Corten steel the same as stainless steel?

No. Corten is a low-alloy weathering steel with small amounts of copper, chromium, nickel and phosphorus. It rusts on purpose, and the rust layer slows further atmospheric corrosion. Stainless steel contains at least about 10.5% chromium and stays bright. For chemical, food or marine service, use stainless steel, not Corten.

How long does Corten steel take to form its patina?

In the open air with regular wet and dry cycles, the rust colour appears within weeks and the protective patina usually stabilises over several months to a few years, depending on climate. Surfaces that stay wet, are sheltered from rain or are exposed to sea salt may not form a stable patina.

What are the equivalent grades of Corten steel?

Corten A is close to ASTM A242 Type 1, EN 10025-5 S355J0WP / S355J2WP and JIS SPA-H. Corten B is close to ASTM A588 Gr A, EN 10025-5 S355J0W / S355J2W / S355K2W and JIS SMA 490. In India, IRSM 41-97 is the Indian Railways corrosion-resistant steel used for wagons. These are close equivalents, not exact matches, so order to the standard your drawing specifies.

What is IRSM 41-97 steel?

IRSM 41-97 is the Indian Railways specification for corrosion-resistant (weathering) steel plates and sheets, used for wagon and coach bodies, roofs and underframes. It is a copper-chromium-nickel-phosphorus steel similar in purpose to Corten A. We supply IRSM 41-97 plates and sheets with mill test certificates.

Can Corten steel plates be welded?

Yes. Corten B / A588 and S355J2W weld well with normal structural practice. Corten A's higher phosphorus makes it better suited to thinner sections. Where the weld must weather to the same colour and resistance as the plate, welders use consumables with matching weathering chemistry, such as AWS E8018-W type electrodes.

Do you supply Corten sheets cut to size for signage and facades?

Yes. We supply Corten sheets and plates in full mill sizes or cut to your sizes for name boards, signage, facade panels, planters and landscape edging. Send a cutting list with quantities. See also our Corten steel signages page.

What is the price of Corten steel plate per kg?

The price depends on the grade, thickness, plate size, quantity, mill and whether cutting is needed, and it moves with steel market prices. Send your grade, sizes and quantity to kamlesh@dineshtube-india.com or call +91 83559 10913 for a current quote.

Which certificates come with your Corten steel plates?

Every supply comes with an EN 10204 3.1 mill test certificate showing heat number, chemical analysis and mechanical test results to the ordered standard. EN 10204 3.2 certificates and third-party inspection can be arranged on request.

Export Destinations for Corten Steel Plates

We supply Corten steel plates across India, including Mumbai, Pune, Delhi NCR, Bengaluru, Chennai, Hyderabad, Ahmedabad and Kolkata, and export to the Middle East (UAE, Saudi Arabia, Qatar, Oman, Kuwait, Bahrain), Africa (Egypt, Nigeria, Kenya, South Africa, Algeria), South and South-East Asia (Sri Lanka, Bangladesh, Nepal, Singapore, Malaysia, Indonesia, Vietnam), Europe (UK, France, Germany, Italy, Netherlands) and the Americas (USA, Canada, Brazil, Mexico) on request.