What is DX51D galvanized steel?
DX51D is EN 10346's entry grade for continuously hot-dip coated low-carbon steel: D for flat products for cold forming, X for the rolling condition not specified (hot- or cold-rolled substrate), 51 for the quality level and D for hot-dip coating. The +Z suffix is the zinc coating, followed by the mass (Z140, Z275). The standard fixes only a maximum tensile strength (500 MPa) and a minimum elongation (22 % A80) — there is no guaranteed yield, which is why DX51D is a bending grade and not a structural one; typical values are 280–320 MPa yield and 350–420 MPa tensile. Carbon is limited to 0.18 %, but real heats run 0.03–0.06 %, so the sheet is soft, ductile and easy to form, roll-form, lock-seam and spot-weld. It is the grade behind trapezoidal roofing, purlins, ducting, cable trays, enclosures, appliance panels and the general galvanized sheet trade; the zinc carries the corrosion protection and Z140 is the Turkish stock standard, Z275 the export standard. Substrate thickness 0.30–4.0 mm (up to 6.0 mm at some mills); above 3 mm the zinc coating adheres less well in tight bends.
Chemical composition
| Element | C | Si | Mn | P | S | Ti |
|---|---|---|---|---|---|---|
| max. % (ladle) | 0.18 | 0.50 | 1.20 | 0.12 | 0.045 | 0.30 |
Typical heat: C 0.04, Mn 0.25, Si 0.02 — much softer than the limits suggest.
Mechanical properties and bendability
| Property | Requirement | Typical value | Note |
|---|---|---|---|
| Yield strength ReH / Rp0.2 | not specified | 280–320 MPa | bending grade |
| Tensile strength Rm | ≤ 500 MPa | 350–420 MPa | |
| Elongation A80 | ≥ 22 % | 28–35 % | 0.70 mm and up; 0.30–0.70 mm on agreement |
| Bend test | 0 × t (180°) | passes | transverse, coating intact |
| Hardness | — | 55–65 HRB |
Equivalent grades
| System | Grade | Note |
|---|---|---|
| EN 10142 (old) | DX51D+Z (EN 10142) | withdrawn 2004 |
| DIN 17162 | St 02 Z+Z (EN 10142) | historic German |
| JIS G3302 | SGCC | |
| ASTM A653 | CS Type B / Commercial Steel | coating G90 ≈ Z275 |
| GB/T 2518 | DX51D+Z |
Zinc coating classes (Z100–Z600)
| Class | Zinc mass (g/m², both sides) | Thickness per side (µm) | Typical life C3 | Where used |
|---|---|---|---|---|
| Z100 | 100 | ≈ 7 | 4–6 years | indoor, painted parts, ducting |
| Z140 | 140 | ≈ 10 | 6–9 years | the Turkish stock standard |
| Z200 | 200 | ≈ 14 | 9–13 years | roofing, outdoor cladding |
| Z275 | 275 | ≈ 20 | 12–18 years | export standard, purlins, structural |
| Z350 | 350 | ≈ 25 | 15–22 years | agriculture, coastal |
| Z450 / Z600 | 450 / 600 | ≈ 32 / 42 | 20–35 years | highway, marine, ground contact |
Life = time to 5 % red rust per ISO 9223 C3 (0.7–2.1 µm zinc loss per year); halve it for C4 industrial-coastal, double it for C2 rural. Spangle: normal (N) or minimised (M); surface quality A (normal) or B (improved, for painting); surface treatment C (chemical passivation), O (oiled), CO (both).
Thickness range and stock sizes
| Thickness | Widths × lengths | Availability |
|---|---|---|
| 0.30–0.50 mm | coil 1 000 / 1 250 mm; sheet 2 000–3 000 mm | stock Z140, Z275 5–10 days |
| 0.60–1.20 mm | coil 1 000 / 1 250 / 1 500 mm; sheet to 6 000 | stock Z140 |
| 1.50–2.50 mm | coil 1 250 / 1 500 mm; sheet 2 500 / 3 000 / 6 000 | stock Z140 |
| 3.0–4.0 mm | coil 1 250 / 1 500 mm; sheet 2 500 / 6 000 | stock, limited |
| slit strip | any width 20–1 500 mm | slitting in Dilovası 3–5 days |
Weight per m² and per sheet
| Thickness | kg/m² | 1 000 × 2 000 (kg) | 1 250 × 2 500 (kg) | 1 500 × 3 000 (kg) |
|---|---|---|---|---|
| 0.3 mm | 2.50 | 5.0 | 7.8 | 11.2 |
| 0.4 mm | 3.28 | 6.6 | 10.3 | 14.8 |
| 0.5 mm | 4.07 | 8.1 | 12.7 | 18.3 |
| 0.6 mm | 4.85 | 9.7 | 15.2 | 21.8 |
| 0.7 mm | 5.64 | 11.3 | 17.6 | 25.4 |
| 0.8 mm | 6.42 | 12.8 | 20.1 | 28.9 |
| 1 mm | 7.99 | 16.0 | 25.0 | 36.0 |
| 1.2 mm | 9.56 | 19.1 | 29.9 | 43.0 |
| 1.5 mm | 11.92 | 23.8 | 37.2 | 53.6 |
| 2 mm | 15.84 | 31.7 | 49.5 | 71.3 |
| 2.5 mm | 19.77 | 39.5 | 61.8 | 88.9 |
| 3 mm | 23.69 | 47.4 | 74.0 | 106.6 |
| 4 mm | 31.54 | 63.1 | 98.6 | 141.9 |
Includes Z140 coating (≈ 0.14 kg/m²); add 0.135 kg/m² for Z275. Tolerances to EN 10143.
Forming, welding and painting
DX51D bends flat on itself (0 × t) at any stock thickness and roll-forms into trapezoidal, C, Z and omega profiles without cracking the zinc; keep tool clearance 8–10 % for punching to avoid zinc pick-up. Spot, seam and MAG welding work with fume extraction (zinc oxide) and slightly higher current; the zinc burns back 1–2 mm from the weld and must be touched up with zinc-rich paint. Lock-seaming, riveting and clinching are preferred for ducts and enclosures. For painting order surface quality B with chemical passivation C or a phosphate-free pretreatment; oiled (O) coils need degreasing. Do not hot-form: zinc melts at 419 °C.
Where it is used
- Trapezoidal and corrugated roofing and cladding sheet
- C and Z purlins, omega and light-gauge framing profiles
- HVAC ducting, plenums and cable trays
- Electrical enclosures, cabinets and appliance panels
- Silo, grain-bin and water-tank panels
- General galvanized sheet for fabrication and export
DX51D vs DX52D / DX53D — which forming grade
DX51D bends; DX52D draws; DX53D deep-draws. If the part is bent, folded or roll-formed, DX51D is the right and cheapest grade. If it is pressed into a shallow pan, a tray or a stiffened panel, DX52D with its guaranteed yield window (140–300 MPa) and 26 % elongation avoids splits. Deep-drawn sinks, cups and automotive-type parts need DX53D or DX54D. For roofing and purlins with a strength requirement the structural S250GD–S350GD grades replace DX51D.
Price
DX51D is the base of the galvanized list. The bands below are the month's indicative FOB Istanbul ranges by thickness — thin gauges cost more per ton because of rolling and zinc share. Z275 adds about 8 % over Z140; slitting and cut-to-length are priced per ton.
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
Packing of DX51D galvanized steel: coils on cradles (eye-to-sky, VCI wrap, four straps, 5–25 t) or sheet packs on skids up to 3 t with interleaving paper and corner protectors; 20' ≈ one coil (≤ 20 t), 40' HC ≈ two coils or 24 t of sheet. Tariff 7210 / 7209 / 7208.
| Term | Detail |
|---|---|
| MOQ | One coil (5–20 t) or 5 t of sheet |
| Incoterms | FOB Istanbul · CIF / CFR Gulf, Africa · DAP EU, Balkans, Iraq, Caucasus · DAP Aktau |
| Lead time | Stock 0.30–4.0 mm Z140: 3–5 working days; Z275 and slit widths 5–10 days |
| Packing | Coil eye-to-sky on cradle, VCI wrap; 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
Documentation for DX51D galvanized steel: EN 10204 3.1 mill certificate as standard (heat number, analysis, tensile, Charpy, condition); 3.2 with an independent inspector, EN 10160 UT reports and additional low-temperature Charpy tests are available on plates above 8 mm at order.
How to order
Specify thickness × width (coil) or × length (sheet), coating (Z140 / Z200 / Z275), spangle (N / M), surface (A / B), treatment (C / O / CO), coil weight limit and tonnage; slit widths and cut lengths are done in Dilovası.
Standards
- EN 10346:2015 — DX51D+Z, 1.0226
- EN 10143 — dimensions and tolerances of coated strip
- EN 10204 3.1
- Former EN 10142 / DIN 17162 St 02 Z
Grades
Grade data sheets (chemistry, mechanicals, equivalents) are on our reference site: DX51D · DX52D · S250GD
Frequently asked questions
What is DX51D material?
The standard hot-dip galvanized low-carbon steel for bending and roll-forming to EN 10346 (material number 1.0226), supplied with a Z100–Z275 zinc coating as coil, sheet or slit strip in 0.30–4.0 mm.
What is the yield strength of DX51D?
EN 10346 does not guarantee a yield value for DX51D — only tensile ≤ 500 MPa and elongation ≥ 22 %; typical yield is 280–320 MPa. For a guaranteed yield use DX52D (140–300 MPa) or the structural S250GD–S350GD grades.
What does DX51D+Z275 mean?
DX51D grade with a hot-dip zinc coating of 275 g/m² total on both sides (about 20 µm per side) — the export standard for roofing and outdoor use; Z140 is the Turkish stock standard.
What is the ASTM equivalent of DX51D?
ASTM A653 CS Type B (Commercial Steel) with G90 coating (≈ Z275); JIS G3302 SGCC is the Japanese equivalent.
Can DX51D be welded?
Yes — spot, seam and MAG welding with fume extraction; the zinc burns back at the weld and is repaired with zinc-rich paint. Lock-seaming and riveting avoid the issue on ducts.
What is the difference between DX51D and DX52D?
DX52D has a guaranteed yield window (140–300 MPa), higher elongation (26 %) and tighter chemistry for drawing; DX51D is the cheaper bending grade without a yield guarantee.