Then purchasing ASTM A606 Type 4 steel, buyers usually need more than a grade name. The key questions are whether the material is genuine Type 4, whether the ordered thickness is hot rolled or cold rolled, whether the sheet is flat enough for fabrication, and whether every batch is supplied with traceable mill documentation.
ASTM A606/A606M covers high-strength, low-alloy sheet and strip in cut lengths or coils. ASTM A606 Type 4 weathering steel uses additional alloying elements and must provide atmospheric corrosion resistance substantially better than carbon steel. Its minimum corrosion-resistance index is commonly specified as 6.0 according to ASTM Guide G101.
ASTM A606 Type 4 Grade, Product Form and Standard
| Buyer confirmation | ASTM A606 Type 4 requirement |
|---|---|
| Exact grade | ASTM A606 Type 4 / ASTM A606M Type 4 |
| Standard edition | ASTM A606/A606M-25 or the edition stated in the contract |
| Certified product form | Hot-rolled or cold-rolled sheet/strip; cut lengths or coils |
| Corrosion performance | Minimum corrosion-resistance index of 6.0 according to ASTM G101 |
| Common surface | Hot-rolled mill finish, pickled, blasted, cold-rolled matte or pre-rusted |
| Documentation | MTC showing heat number, chemistry, tensile results and product dimensions |
The commercial term "A606 Type 4 plate" is widely used, but the formal standard mainly covers sheet and strip. Under ASTM A606/A606M-25, hot-rolled cut lengths are covered below 0.230 in. [6.0 mm], while hot-rolled coils may be ordered at 6.0 mm and above. Thick structural plate should be reviewed against ASTM A588, ASTM A871 or the project specification.
ASTM A606 Type 4 Hot-Rolled and Cold-Rolled Sizes
For buyers using 1.5–5 mm sheet, the rolling route and flatness are often more important than a broad theoretical size range.
| ASTM A606 Type 4 supply item | Practical sourcing range |
|---|---|
| Cold-rolled sheet/coil | Approximately 0.5–3.0 mm thick; width commonly 600–1,500 mm |
| Hot-rolled sheet/coil | Approximately 1.5–10.0 mm thick; width commonly 800–1,900 mm |
| Common cut sheets | 1,219 × 2,438 mm, 1,250 × 2,500 mm, 1,500 × 3,000 mm |
| Edge condition | Mill edge, slit edge or cut edge |
| Dimensional control | ASTM A568/A568M or the agreed purchase specification |
A quotation should state the thickness tolerance, width/length tolerance and flatness requirement. True 3 mm does not mean every measured point is exactly 3.000 mm; the acceptable tolerance class must be written into the order.
Thin sheets cut from coil may retain coil set or release residual stress during laser cutting, so levelling and finished-part inspection should be agreed in advance.
ASTM A606 Type 4 Chemical and Mechanical Data
The simplified chemical table below shows the general limits commonly used for ASTM A606 Type 4. Type 4 compliance also requires the mill-selected weathering alloy system and corrosion-index evidence; fixed Cu, Cr and Ni ranges should not be assumed for every producer.
| ASTM A606 Type 4 chemical item | Heat analysis | Product analysis |
|---|---|---|
| Carbon, max. | 0.22% | 0.26% |
| Manganese, max. | 1.25% | 1.30% |
| Sulfur, max. | 0.040% | 0.060% |
| Weathering elements | Mill-designed Cu/Cr/Ni/Si/P combination | Verified through MTC and G101 calculation |
| ASTM A606 Type 4 condition | Yield strength, min. | Tensile strength, min. | Elongation, min. |
|---|---|---|---|
| Hot rolled, as rolled | 50 ksi [340 MPa] | 70 ksi [480 MPa] | 22% |
| Hot rolled, annealed/normalized | 45 ksi [310 MPa] | 65 ksi [450 MPa] | 22% |
| Cold rolled | 45 ksi [310 MPa] | 65 ksi [450 MPa] | 22%* |
Cold-rolled material approximately 1.1 mm and thinner has a referenced minimum elongation of 20%. The supplier reference page separates plate and coil properties, but the more important distinction is the actual rolling and delivery condition shown on the MTC.
ASTM A606 Type 4 Processing, MTC and Inspection
GNEE can provide coil slitting, cut-to-length, levelling, laser cutting, shearing, perforating, bending, welding, shot blasting and pre-rusting. For visible panels, Pre-Rusted Corten Steel or Pre-Weathered Corten Steel can shorten the initial site-weathering period, but these terms describe the surface rather than the substrate grade.
| ASTM A606 Type 4 buyer document | What it should confirm |
|---|---|
| EN 10204 3.1 MTC/mill report | Grade, standard edition, heat number, dimensions and tensile results |
| Heat analysis | C, Mn, S and the mill's weathering alloy design |
| ASTM G101 evidence | Type 4 corrosion-resistance index |
| Dimensional report | Actual thickness, width, length and flatness |
| Processing report | Cut size, hole position, bending or first-piece inspection |
| Third-party inspection | SGS, BV or another agreed agency when required |
Send your MTC and inspection checklist before ordering. We can include the documentation scope, inspection cost and witness points in the quotation instead of adding them after production.
ASTM A606 Type 4 Sheet Weight and Container Quantity
Theoretical weight is calculated using 7,850 kg/m³:
Weight (kg) = thickness (mm) × width (m) × length (m) × 7.85
| ASTM A606 Type 4 size | Weight per sheet | Approx. sheets at 25 t net weight* |
|---|---|---|
| 2 × 1,250 × 2,500 mm | 49.1 kg | 509 |
| 3 × 1,250 × 2,500 mm | 73.6 kg | 339 |
| 3 × 1,500 × 3,000 mm | 106.0 kg | 235 |
| 5 × 1,500 × 3,000 mm | 176.6 kg | 141 |
*Indicative only. Final loading depends on actual thickness, pallets, packaging, container payload and local transport rules. A 20-foot container commonly carries about 24–27 tonnes of steel.
ASTM A606 Type 4 Best-Value Quotation
For the lowest practical landed cost, buyers should allow the supplier to compare standard coil widths, mill cut lengths and custom processing rather than fixing only one unusual size. GNEE can quote FOB, CIF and DAP and show the material weight, cutting loss, packing and freight separately.
Stock material may be prepared in approximately 7–15 days; mill or processed orders commonly require 20–40 days. Samples can be provided for material verification, forming, welding or patina approval.
Send your size list and destination. We will return the recommended standard size, theoretical weight, container plan, MTC scope, lead time and FOB/CIF/DAP price in one quotation.
Contact ASTM A606 Type 4 Weathering Steel Stocklist
