What is S355 structural steel?
S355 is the reference high-strength low-alloy structural steel of the EN 10025-2 standard, with a minimum yield strength of 355 MPa up to 16 mm thickness. The suffix letter defines the impact-toughness class: JR is tested at +20 °C, J0 at 0 °C, and J2 at −20 °C (27 J); S355K2 delivers 40 J at −20 °C for critical welded structures. It is the default structural grade for buildings, bridges, cranes and heavy machinery across Europe, the Middle East, Africa and Southeast Asia, and one of the most searched steel grades worldwide.
S355JR vs S355J0 vs S355J2 vs S355K2
| Grade | Impact test | Impact energy | Typical use |
|---|---|---|---|
| S355JR | +20 °C | 27 J | Buildings, general welded structures |
| S355J0 | 0 °C | 27 J | Structures in cold regions |
| S355J2 | −20 °C | 27 J | Bridges, cranes, dynamically loaded structures |
| S355K2 | −20 °C | 40 J | Critical welds, low-temperature duty |
Chemical composition (EN 10025-2, max %)
| Grade | C max | Si max | Mn max | P max | S max | CEV max |
|---|---|---|---|---|---|---|
| S355JR / J0 / J2 / K2 | 0.24 | 0.55 | 1.60 | 0.035 | 0.035 | 0.45 |
Real mill data — Baosteel MTC
Actual ladle analysis and mechanical results from recent Baosteel shipments, certificate numbers as issued:
| Certificate | Size (mm) | C % | Si % | Mn % | P % | S % | CEQ | Yield MPa | Tensile MPa | EL % |
|---|---|---|---|---|---|---|---|---|---|---|
| S355JR · BGSAI2610231300400 | 5.00 × 1500 × 6000 | 0.16 | 0.13 | 0.37 | 0.015 | 0.005 | 0.23 | 417 | 517 | 34 |
| S355J2 · BGSAI2608312366800 | 4.00 × 1500 × 6000 | 0.17 | 0.14 | 0.39 | 0.018 | 0.007 | 0.24 | 434 | 549 | 32 |
Download the watermarked samples: Sample MTC (S355JR 5 mm) · Sample MTC (S355J2 4 mm, with CPR Declaration of Performance). Original EN 10204 3.1 certificates accompany every shipment.
Global equivalent grades
| Standard | Grade | Notes |
|---|---|---|
| EN 10025-2 (Europe) | S355JR / S355J0 / S355J2 / S355K2 | This product |
| ASTM A572 (USA) | Gr 50 | Closest US grade — see our A572 page |
| GB/T 1591 (China) | Q355B / Q355D | Chinese equivalent — 09G2S / Q355D |
| GOST 19281 (CIS) | 09Г2С | Russian grade, same strength class |
Stock, certificates and delivery
S355JR and S355J2 plates are available ex-stock at our Shanghai warehouse in the certificate sizes above (4–6 mm × 1500 mm × 3000–6000 mm); other thicknesses and cut-to-size pieces on request. Every shipment includes the original Baosteel mill test certificate to EN 10204 3.1 with heat number, chemistry and mechanical results. EXW, FOB Shanghai, CFR and CIF terms available; shipments leave within 7 days of payment.
