The original A 242 alloy has a yield strength of 50,000 pounds per square inch (340,000 kPa) and ultimate tensile strength of 70,000 psi (480,000 kPa) for light-medium rolled shapes and plates up to 0.75 inches (19 mm) thick. It has yield strength of 46,000 psi (320,000 kPa) and ultimate strength of 67,000 psi (460,000 kPa) for medium weight rolled shapes and plates from 0.75–1 inch (19–25 mm) thick. The thickest rolled sections and plates – from 1.5–4 in (38–100 mm) thick have yield strength of 42,000 psi (290,000 kPa) and ultimate strength of 63,000 psi (430,000 kPa).
Reading the units: The page gives each strength in psi and, in brackets, in kPa. Rounded, these are 345 / 485 MPa for the thin plate, 320 / 460 MPa for the medium band and 290 / 430 MPa for the thickest plate; “340,000 kPa” is a rounding of 345 MPa.
Missing thickness band: The page lists 0.75–1 in (19–25 mm) and then 1.5–4 in (38–100 mm), leaving 1–1.5 in (25–38 mm) unstated. ASTM A242 places the middle band up to 1.5 in (38 mm), so the 25 mm in the original appears to stop short. See the table below.
ASTM A242 Strength by Thickness
| Plate thickness | Minimum yield strength | Minimum tensile strength |
|---|---|---|
| Up to 0.75 in (19 mm) | 50,000 psi (about 345 MPa) | 70,000 psi (about 485 MPa) |
| 0.75–1 in (19–25 mm), as the page states | 46,000 psi (about 320 MPa) | 67,000 psi (about 460 MPa) |
| 1.5–4 in (38–100 mm) | 42,000 psi (about 290 MPa) | 63,000 psi (about 430 MPa) |
Rearranged from the paragraph above. The page gives no band for 1–1.5 in (25–38 mm); in ASTM A242 the middle band runs up to 1.5 in (38 mm), so read the 46 ksi / 67 ksi row as covering that range. Confirm the values for your thickness on the mill certificate.
ASTM A 242 Corten Plates: Purchasing Specification
| Requirement | What to specify |
|---|---|
| Grade and standard | Corten A (ASTM A242), Corten B / ASTM A588 Grade A or S355J0W (EN 10025-5); say which standard your drawing cites and any quality such as J0 or J2. |
| Thickness | Give the thickness range of your parts; minimum yield falls as plate gets thicker, so check the certificate for heavy plate. |
| Exposure | Where the plate will stand, whether it will be painted, and whether it stays wet or sees salt or de-icing chemicals. |
| Cutting | Plasma or oxy-fuel cutting to your drawing; give hole positions, edge preparation and tolerances. |
| Welding | A qualified procedure; for welds left bare outdoors ask for filler metal that weathers like the plate, and follow the mill’s preheat advice. |
| Documents | Mill test certificate (EN 10204 3.1) with chemistry and mechanical properties, plus impact results if you specify a test temperature. |
How the Four Corten Pages Differ
The four pages cover weathering steel, the type known as Corten, under different names and standards: Corten A, ASTM A588 Grade A, ASTM A242 and the EN S355J0W grade. All form a protective rust-like layer when left exposed to the weather; the pages differ in the standard they describe and the data they give.
| Page | What it covers | Typical use (from the pages) |
|---|---|---|
| CORTEN A | Corten A features and applications, with a chemistry table | Containers, rolling stock, oil rigs, harbour construction, oil platforms |
| A588 | ASTM A588 Grade A to 100 mm: 50 ksi yield, 70 ksi tensile, gauge and stock-length table | Welded bridges and buildings, bare (unpainted) structures |
| A242 (this page) | The original A242 alloy, with yield and tensile strength by thickness band | Rolled shapes and plates up to 4 in (100 mm) |
| S355J0W | EN S355 weathering grades with Corten A/B, SAILCOR, IRS M41 and JIS SPA-H names, scope and definition | Body structures, bridges, tanks and bins, exhaust systems, vehicles |
State the standard and grade on your enquiry; these names describe the same type of steel but are not identical.
Related plates in this range
Applications for ASTM A 242 Corten Plates
Typical uses include bridges, buildings, containers, rolling stock, oil platforms, tanks and other welded structures left unpainted outdoors. Tell us the load, temperature and service conditions so the right grade and thickness can be quoted.
Cutting, Fabrication and Welding
Champak Industries describes full and part plate/profile supply and a plasma-cutting service. Send drawings, quantities, tolerances and edge preparation for your parts. Corten plate can be cut by plasma or oxy-fuel and welded with a qualified procedure. Ask for weathering-type filler metal where welds will be left bare outdoors, follow the mill’s advice on preheat, and send the grade and thickness with the drawing.
Testing, Inspection Documents and Traceability
| Requirement | What to identify in the order |
|---|---|
| Mill test certificate | EN 10204 3.1 showing brand and grade, heat number, chemistry and mechanical properties |
| Impact test | Charpy test temperature and minimum energy, if required |
| Ultrasonic test | Standard and acceptance class, if required |
| Traceability | Heat and plate number transferred to cut pieces |
See the company’s Quality Policy for its published policy.
Source ASTM A 242 Corten Plates from Champak Industries
Champak Industries’ company profile records its establishment in Mumbai in 1978 and its stockist, import and export activities. ASTM A 242 Corten Plates can be requested together with other plates in the Corten Plates range.
What Determines the Quotation?
Grade and brand, thickness, plate size, quantity, cutting, testing and packing all affect the quotation. Say whether pricing is needed per kilogram, per plate or per finished piece.
Packing, Dispatch and Export Requirements
Give the delivery address, required date and unloading constraints. For export orders, include the destination port, delivery terms and document list.
ASTM A 242 Corten Plates: Frequently Asked Questions
01What is ASTM A 242 Corten Plates?
ASTM A242 is the original Corten alloy, a weathering structural steel with 50 ksi (345 MPa) minimum yield and 70 ksi (485 MPa) minimum tensile strength for plate up to 0.75 in (19 mm), with lower minimums for thicker plate.
02What strength does A242 have for thin plate?
The page lists 50,000 psi (345 MPa) minimum yield and 70,000 psi (485 MPa) minimum tensile strength for plate up to 0.75 inch (19 mm).
03Does strength fall as plate gets thicker?
Yes. The page lists 46,000 psi yield and 67,000 psi tensile for medium-weight plate, and 42,000 psi and 63,000 psi for the thickest plate, 1.5 to 4 inch (38–100 mm).
04Is A242 the same as Corten A?
The Corten Plates page names A242 as the original “Corten A” specification: A242 is the standard and Corten A is the trade name.
05Can ASTM A242 be welded?
Yes, with a qualified procedure. For parts left bare outdoors, ask for filler metal that weathers like the plate, and follow the mill’s advice on preheat and heat input.
06Which certificate should I request?
An EN 10204 3.1 mill test certificate showing the brand and grade, heat number, chemistry and mechanical properties, plus impact results where you specify a test temperature.
07Can another brand replace ASTM A242?
Brands of the same class are comparable, not identical. Chemistry, toughness, thickness range and processing advice differ by mill, so confirm any substitution with your engineer.
08Can ASTM A242 plate be cut to size?
Yes. Champak Industries lists full and part plate and profile supply and a plasma-cutting service; send drawings, quantities and tolerances with your enquiry.
09Which sizes are available?
Availability depends on the grade, mill and thickness; send the thickness, width and length you need and sizes will be confirmed at quotation.
10How do I get a price and delivery date?
Send the grade, thickness, size or cutting drawing, quantity, destination and required date through the enquiry form below, by WhatsApp or by phone.