What is S700MC steel?
S700MC reaches 700 MPa yield without quenching: a thermomechanical rolling schedule on a low-carbon steel alloyed with niobium, titanium, vanadium plus up to 0.50 % molybdenum and 0.005 % boron produces a very fine bainitic-ferritic grain. The result is a strip with the strength of a quenched-and-tempered S690 plate but the weldability of a mild steel (CEV ≈ 0.40, no preheat) and guaranteed cold-forming radii — 1.5 × t up to 3 mm and 2.0 × t above, transverse. Charpy 40 J at −20 °C longitudinal. It is produced only as hot-rolled strip, typically 3–12 mm (up to 16–20 mm at some mills), and it must never be hot-formed, normalised or stress-relieved above 580 °C, because the microstructure that carries the strength would be destroyed. Designers know it under the SSAB names Strenx 700MC / Domex 700MC or the old QStE 690 TM; the EN grade is what appears on the certificate.
Chemical composition
| Element | C | Si | Mn | P | S | Al | Nb | V | Ti | Mo | B |
|---|---|---|---|---|---|---|---|---|---|---|---|
| max. % (ladle) | 0.12 | 0.60 | 2.10 | 0.025 | 0.015 | ≥ 0.015 | 0.09 | 0.20 | 0.22 | 0.50 | 0.005 |
Nb + V + Ti ≤ 0.22 %. CEV typically 0.38–0.42.
Mechanical properties
| Thickness | Yield ReH min (MPa) | Tensile Rm (MPa) | Elongation min | Impact KV |
|---|---|---|---|---|
| 1.5–3 mm | 700 | 750–950 | 10 (A80) | — |
| > 3 mm | 700 | 750–950 | 14 % (A5) | 40 J at −20 °C (long.) |
Equivalent grades
| System | Grade | Note |
|---|---|---|
| SEW 092 | QStE 690 TM | old German name |
| EN 10025-6 | S690QL (QT plate) | same strength, plate, needs preheat |
| ASTM | A1011 HSLAS-F Gr. 80 / A656 Gr. 80 | near, 550 MPa |
| SSAB | Strenx 700MC / Domex 700MC | brand |
| JIS | SPFH 780 (near) |
Thickness range and stock sizes
| Thickness | Widths × lengths | Availability |
|---|---|---|
| 3–5 mm | coil 1 000–1 500 mm; sheet to 6 000 | to order 3–5 weeks |
| 6–8 mm | coil 1 250–1 500 mm; sheet 1 500 × 6 000 | to order 3–5 weeks |
| 10–12 mm | coil 1 500 mm; sheet 1 500 × 6 000 | to order 4–5 weeks |
Weight per m² and per plate
| Thickness | kg/m² | 1 500 × 6 000 (kg) | 2 000 × 6 000 (kg) | 2 500 × 12 000 (kg) |
|---|---|---|---|---|
| 3 mm | 23.6 | 212 | 283 | 707 |
| 4 mm | 31.4 | 283 | 377 | 942 |
| 5 mm | 39.3 | 353 | 471 | 1 178 |
| 6 mm | 47.1 | 424 | 565 | 1 413 |
| 8 mm | 62.8 | 565 | 754 | 1 884 |
| 10 mm | 78.5 | 707 | 942 | 2 355 |
| 12 mm | 94.2 | 848 | 1 130 | 2 826 |
Nominal weights — mill tolerance to EN 10029 class A adds up to +4 % on thin plate; invoiced on theoretical weight unless agreed otherwise.
Welding, cutting and forming
Bending: inside radius 1.5 × t (≤ 3 mm) / 2.0 × t (> 3 mm) transverse, 3 × t longitudinal, with a wide die opening (≥ 10 × t), deburred edges and burr inside; spring-back is large (8–12°) — over-bend or air-bend to angle. Punching is possible with clearance 12–15 % and sharp tools; laser and plasma are preferred. Welding: no preheat up to 12 mm; use under-matching G50/G55 or matching G69 consumables depending on design, heat input 0.5–1.2 kJ/mm, interpass ≤ 150 °C — a soft HAZ from excessive heat is the typical failure. Never hot-form, flame-straighten above 600 °C or stress-relieve.
Where it is used
- Telescopic and lattice crane booms, concrete-pump booms
- Aerial work platform arms
- Lightweight semi-trailer chassis and side rails
- Truck frame reinforcements and sub-frames
- Forestry and mining machine structures
- Container chassis and lifting attachments
S700MC vs S690QL
Same strength, two routes. S690QL (EN 10025-6) is a quenched-and-tempered plate: 4–150 mm, needs 100–150 °C preheat and careful procedures, bends at 3–4 × t, but exists in heavy gauges. S700MC is a thermomechanical strip: 3–12 mm, no preheat, bends at 2 × t, cheaper per ton, but cannot be hot-formed and does not exist as heavy plate. Booms and chassis in ≤ 12 mm are S700MC territory; thick lifting lugs, crane pedestals and wear-exposed structures are S690QL. One step down, S500MC is the value grade.
Price
S700MC carries about 250 USD/t over the S235JR base — the highest premium in the hot-rolled list, driven by Mo alloying and mill routing. The band below is the indicative FOB Istanbul range for coil; sheet adds cut-to-length.
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 ship S700MC steel in strapped skid packs up to 5 t, each plate stencilled with its heat number so the certificate can be matched at the receiving end. Six-metre plate loads 24–25 t into a 40' HC. Plates longer than 6 m or heavier packs are booked on flat-racks or as breakbulk cargo out of Derince. Tariff heading 7208.51 / 7208.52.
| Term | Detail |
|---|---|
| MOQ | One coil (≈ 15–20 t) |
| Incoterms | FOB Istanbul · CIF / CFR Gulf, Africa · DAP EU, Balkans, Iraq, Caucasus · DAP Aktau |
| Lead time | To order 3–5 weeks; cut sheet +5 days |
| Packing | Coil eye-to-sky, VCI wrap; sheet on skids |
| Container / truck | 20' one coil; 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
S700MC 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
Send thickness × width (× length), tonnage, the bending direction if critical, and surface requirement (black / pickled). We confirm the mill slot and ship with 3.1 certificates showing Mo and B analysis.
Standards
- EN 10149-2:2013 — S700MC, 1.8974
- EN 10051 tolerances
- EN 10204 3.1
- Former SEW 092 QStE 690 TM
Grades
Grade data sheets (chemistry, mechanicals, equivalents) are on our reference site: S700MC · S500MC · S690QL
Frequently asked questions
What is steel grade 700?
Usually S700MC — the EN 10149-2 thermomechanical hot-rolled strip with 700 MPa minimum yield, material number 1.8974; the brand names Strenx 700MC and Domex 700MC describe the same class.
What is Strenx 700 material?
SSAB's trade name for its 700 MPa steels; Strenx 700MC corresponds to EN 10149-2 S700MC (cold-forming strip) and Strenx 700 E/F to S690QL-type QT plate.
Can S700MC be welded without preheating?
Yes up to 12 mm (CEV ≈ 0.40); the risk is not cracking but softening — keep heat input at 0.5–1.2 kJ/mm and interpass below 150 °C.
What is the minimum bend radius of S700MC?
1.5 × t up to 3 mm and 2.0 × t above 3 mm transverse to rolling (3 × t longitudinal), per EN 10149-2, with deburred edges and burr on the inside.
What is the equivalent of S700MC in ASTM?
There is no exact ASTM equivalent; A656 Grade 80 (550 MPa) and A1011 HSLAS-F Grade 80 are the nearest sheet grades, A514 the nearest plate.
Why must S700MC not be heat treated?
Its strength comes from the fine grain created by thermomechanical rolling; heating above about 600 °C coarsens the grain and the yield can drop by 100–200 MPa.