What is DD11 forming steel?
EN 10111 covers continuously hot-rolled low-carbon sheet and strip for cold forming, in four levels: DD11 (bending), DD12 (drawing), DD13 (deep drawing) and DD14 (extra-deep drawing). DD11 is the workhorse — D for cold-forming flat products, D for hot-rolled, 11 for the base level. The standard sets a yield *window* (170–340 MPa, 360 max below 2 mm), a tensile ceiling (440 MPa) and 28 % elongation, with carbon limited to 0.12 % and manganese to 0.60 %; that window is what distinguishes it from S235JR, whose yield has a floor but no ceiling and which may therefore arrive hard. DD11 is soft and consistent: it bends at 0.5 × t, flanges, swages, roll-forms and forms tubes without cracking, and it cold-works predictably in a progressive die. It is not a structural grade — EN 1993 does not list it — but most formed parts are not designed by yield anyway. Turkish mills roll it in 1.5–12 mm and supply it black or pickled and oiled (HRPO); we stock the pickled 1.5–4 mm for press shops and roll-formers and the black 4–6 mm for heavy brackets. Old names: StW 22 (DIN 1614), St 33 / A1011 CS in other systems.
Chemical composition
| Element | C | Mn | P | S |
|---|---|---|---|---|
| max. % (ladle) | 0.12 | 0.60 | 0.045 | 0.045 |
Typical heat: C 0.04–0.07, Mn 0.25–0.40, Si ≤ 0.03.
Mechanical properties and formability
| Property | Requirement | Typical value | Note |
|---|---|---|---|
| Yield strength ReH | 170–340 MPa (≤ 360 below 2 mm) | 220–290 MPa | window, not a minimum |
| Tensile strength Rm | ≤ 440 MPa | 340–400 MPa | |
| Elongation A80 | ≥ 28 % (≥ 2 mm: A5 ≥ 24 %) | 30–36 % | |
| Bend radius (180°) | 0.5 × t transverse | passes | |
| Hardness | — | 60–70 HRB |
Equivalent grades
| System | Grade | Note |
|---|---|---|
| DIN 1614-1 (old) | StW 22 | historic German |
| EN 10111 (1998) | DD11 | previous edition |
| JIS G3131 | SPHC | |
| ASTM A1011 | CS Type B | |
| GB/T 3273 / 5213 | Q195 / SPHC |
Pickling, oiling and surface
| Condition | Process | Surface | Best for |
|---|---|---|---|
| Black (HR, as-rolled) | none — mill scale left on | blue-black oxide, 10–40 µm, flakes when bent | welded structures, plate to be blasted, hidden parts |
| HRPO (pickled & oiled) | HCl pickling of coil, rinse, light oil | uniform grey-metallic, scale-free, Ra ≈ 1–3 µm | forming, painting, roll-forming, tube making, visible parts |
| HRP / HRPO skin-passed | pickling + temper pass | flatter, tighter gauge, no Lüders lines | pressing, blanking, precision parts |
| Dry (pickled, unoiled) | pickling, no oil | bare, rusts within days | immediate galvanizing or welding only |
Turkish trade names: siyah sac = black hot-rolled, HRP / asitli sac = pickled & oiled. The steel grade (S235JR, DD11 …) is the same under both surfaces; only the finish differs.
Thickness range and stock sizes
| Thickness | Widths × lengths | Availability |
|---|---|---|
| 1.5–2.0 mm | coil 1 000 / 1 250 / 1 500 mm; slit strips | stock HRPO |
| 2.5–4.0 mm | coil 1 250 / 1 500 mm; sheet 2 500 / 3 000 | stock HRPO and black |
| 5.0–6.0 mm | coil 1 500 mm; sheet 1 500 × 6 000 | stock black |
| 8–12 mm | coil / sheet | to order 2–3 weeks |
Weight per m² and per sheet
| Thickness | kg/m² | 1 000 × 2 000 (kg) | 1 250 × 2 500 (kg) | 1 500 × 3 000 (kg) |
|---|---|---|---|---|
| 1.5 mm | 11.78 | 23.6 | 36.8 | 53.0 |
| 2 mm | 15.70 | 31.4 | 49.1 | 70.7 |
| 2.5 mm | 19.63 | 39.3 | 61.3 | 88.3 |
| 3 mm | 23.55 | 47.1 | 73.6 | 106.0 |
| 4 mm | 31.40 | 62.8 | 98.1 | 141.3 |
| 5 mm | 39.25 | 78.5 | 122.7 | 176.6 |
| 6 mm | 47.10 | 94.2 | 147.2 | 212.0 |
| 8 mm | 62.80 | 125.6 | 196.3 | 282.6 |
| 10 mm | 78.50 | 157.0 | 245.3 | 353.3 |
| 12 mm | 94.20 | 188.4 | 294.4 | 423.9 |
Uncoated; tolerances to EN 10051.
Forming, welding and painting
Bends at 0.5 × t in any direction; flanges, hems and swages without cracking; roll-forms and tube-welds like S235JR but with less spring-back variation from coil to coil. Punching clearance 6–8 %. Welds without preheat with any process; the low carbon gives soft, ductile welds. Painting after degreasing (HRPO) or blasting (black). Not for structural design to Eurocode — order S235JR where a minimum yield is needed.
Where it is used
- Pressed brackets, flanges and cross-members for trailers and bodies
- Roll-formed profiles and welded tubes
- Agricultural machinery covers and formed parts
- Wheel rims and drums (with DD12/DD13 for deeper draws)
- Enclosure and cabinet parts in 2–4 mm
- General cold-formed sheet-metal work
DD11 vs S235JR
Same price, same chemistry class, different guarantee. S235JR guarantees strength (yield ≥ 235 MPa, impact 27 J) for structures; DD11 guarantees formability (yield capped at 340 MPa, 28 % elongation, 0.5 × t bend). A hard S235JR heat can crack in a tight bend; a soft DD11 heat cannot be used in a Eurocode calculation. Order by what the part does. For deeper forming move to DD12 or DD13; for strength with formability, S355MC.
Price
DD11 is priced on the hot-rolled coil list — black at the S235JR base, HRPO plus the pickling charge. The bands below are the month's indicative FOB Istanbul ranges for thin (mostly HRPO) and thick (mostly black) stock.
Bands from our weekly export list (September 2026), FOB Istanbul, full-container quantities, excluding freight and certificates. Firm price per project on RFQ within one working day.
Export and packing
We load DD11 forming steel as slit or master coils on cradles (VCI paper, strapped, 5–25 t) or as cut-to-length sheet on skids (≤ 3 t, interleaved, edge boards); a 20' container carries one coil to 20 t, a 40' HC two coils or 24 t of sheet. HS 7210 / 7209 / 7208.
| Term | Detail |
|---|---|
| MOQ | One coil (10–25 t) or 5 t of sheet |
| Incoterms | FOB Istanbul · CIF / CFR Gulf, Africa · DAP EU, Balkans, Iraq, Caucasus · DAP Aktau |
| Lead time | Stock 1.5–6 mm: 3–5 working days; 8–12 mm to order 2–3 weeks |
| Packing | Coil eye-to-sky, VCI paper (HRPO); sheet on skids ≤ 3 t |
| Container / truck | 20' one coil ≤ 20 t; 40' HC two coils or 24 t sheet |
| Documents | Invoice, packing list, EN 10204 3.1 (3.2 on request), certificate of origin; SASO / SONCAP / PVoC on request |
| Payment | 30% advance, balance against B/L copy; L/C at sight for orders above 100 t |
Certificates and testing
DD11 forming steel ships with EN 10204 3.1 certificates cross-referenced to the stencilled heat numbers. Where the project requires it we arrange 3.2 certification with Lloyd's, BV, TÜV or SGS, ultrasonic examination to EN 10160 and Charpy testing at the temperature you specify.
How to order
Specify thickness × width (× length), surface (black / HRPO), coil or sheet, tonnage and the forming operation; we advise if DD12–DD14 or an MC grade suits the part better.
Standards
- EN 10111:2008 — DD11, 1.0332
- EN 10051 — tolerances
- EN 10204 3.1
- Former DIN 1614 StW 22 / EN 10111 (1998) DD11
Grades
Grade data sheets (chemistry, mechanicals, equivalents) are on our reference site: DD11 · DD12 · DD13
Frequently asked questions
What is DD11 steel?
A hot-rolled low-carbon steel for cold forming to EN 10111 (1.0332, ex StW 22): yield 170–340 MPa, tensile ≤ 440 MPa, elongation ≥ 28 %, bend 0.5 × t — the bending and roll-forming grade, supplied black or pickled and oiled.
What is the difference between DD11 and S235JR?
S235JR is a structural grade with a minimum yield and impact test; DD11 is a forming grade with a yield window (170–340 MPa) and guaranteed elongation. Same chemistry class and price; choose by whether the part is designed for strength or formed.
What is the equivalent of DD11?
DIN StW 22, JIS SPHC, ASTM A1011 CS Type B, GB Q195 — all commercial-quality hot-rolled forming sheet.
Is DD11 available pickled and oiled?
Yes — DD11 HRPO 1.5–4 mm is a stock item at Dilovası; black DD11 in 4–6 mm; thicker to order.
Can DD11 be welded?
Yes, with any process and without preheat; carbon is at most 0.12 %.