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
S700MC steel is packed as follows: coil eye-to-sky, VCI wrap; sheet on skids. Loading: 20' one coil; 40' HC two coils or 24 t sheet. Tariff heading follows the surface: 7208 hot-rolled, 7209 cold-rolled, 7210 coated, 7225 / 7226 alloy.
| 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
The paperwork travelling with S700MC steel is an EN 10204 3.1 certificate covering chemistry, mechanical values and the delivery condition. On request we add 3.2 witnessing by a classification society or an independent inspector. Ultrasonic testing to EN 10160 and extra Charpy tests at a lower temperature are priced separately.
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.