S355J2 steel (1.0577): properties, composition, equivalents
S355J2 (1.0577): 355 MPa yield, 470–630 MPa tensile, 27 J Charpy at −20 °C. The plate grade for cranes, bridges and machinery — full composition, thickness table, equivalents (A572, Q355D, SM490).
What is S355J2?
S355J2 is the plate grade engineers actually specify when they write "S355": 355 MPa minimum yield, 470–630 MPa tensile and a Charpy guarantee of 27 J at −20 °C, Werkstoff number 1.0577. The J2 suffix also brings tighter cleanliness (P, S ≤ 0.025 %) and mandatory full killing, so the steel is more uniform than S355JR from the same mill.
Most S355J2 plate is delivered normalized or normalizing-rolled (+N), giving a fine ferrite–pearlite structure that keeps toughness in thicknesses up to 250 mm. Crane makers, bridge fabricators and machinery builders standardize on it because it covers most temperate-climate service without moving to the fine-grain S355N/NL family of EN 10025-3.
Old drawings call it St52-3 N or Fe510D; in the United States ASTM A572 Grade 50 with Charpy supplement (or A709-50 for bridges) is the practical equivalent, and in China Q355D.
S355J2 chemical composition
| Element | Mass % | Note |
|---|---|---|
| C | ≤ 0.22 | ≤ 30 mm; 0.22 % above 30 mm |
| Si | ≤ 0.55 | |
| Mn | ≤ 1.6 | |
| P | ≤ 0.025 | |
| S | ≤ 0.025 | |
| Cu | ≤ 0.55 |
Ladle analysis, EN 10025-2:2019 Table 2. Fully killed (FF). No N limit because Al-killed. CEV max 0.45 % (≤ 30 mm) to 0.47 % (40–150 mm).
S355J2 mechanical properties
| Thickness / condition | Yield strength ReH / Rp0.2 MPa (ksi) | Tensile strength Rm MPa (ksi) | Elongation A % | Hardness |
|---|---|---|---|---|
| ≤ 16 mm | 355 (51.5) | 470–630 (68.2–91.4) | 22 | ≈ 150–190 HB (typical) |
| > 16 ≤ 40 mm | 345 (50.0) | 470–630 (68.2–91.4) | 22 | — |
| > 40 ≤ 63 mm | 335 (48.6) | 470–630 (68.2–91.4) | 21 | — |
| > 63 ≤ 80 mm | 325 (47.1) | 470–630 (68.2–91.4) | 20 | — |
| > 80 ≤ 100 mm | 315 (45.7) | 470–630 (68.2–91.4) | 20 | — |
| > 100 ≤ 150 mm | 295 (42.8) | 450–600 (65.3–87.0) | 18 | — |
| > 150 ≤ 200 mm | 285 (41.3) | 450–600 (65.3–87.0) | 17 | — |
| > 200 ≤ 250 mm | 275 (39.9) | 450–600 (65.3–87.0) | 17 | — |
Same strength table as S355JR/J0/K2. Elongation longitudinal, L0 = 5.65√S0.
Impact toughness
S355J2 requires a minimum Charpy V-notch energy of 27 J at -20 °C (longitudinal). S355K2 (1.0596) requires 40 J at −20 °C; S355J2 is the standard ordering grade for plate.
S355J2 equivalent grades
| Grade | System | Match | Why / differences |
|---|---|---|---|
| St52-3 | DIN (superseded German) | Identical | Successor of St52-3 N (1.0577); same yield table, tensile 470–630 MPa, 27 J at −20 °C, cleaner P/S. |
| S355J2H | EN (European) | Identical | Same steel as plate, strip and sections to EN 10025-2; H marks the hollow-section standard. |
| A572 Gr. 50 | ASTM / ASME | Near | Yield 345 MPa, Rm 450 MPa min; order with supplementary S5 (Charpy) to approach J2 toughness. |
| A709 Gr. 50 | ASTM / ASME | Near | Bridge version of A572-50 with Charpy requirement by zone; closest US match for bridge plate. |
| S355JR | EN (European) | Near | Same strength; JR tested at +20 °C, higher P/S allowed. |
| S355N | EN (European) | Near | EN 10025-3 normalized fine-grain steel, same strength up to 16 mm, better guaranteed toughness and weldability (Nb/V/Ti grain refinement). |
| Q355D | GB/T (China) | Near | GB/T 1591 Q355D: 355 MPa yield, 34 J at −20 °C; quality D is the −20 °C class matching J2. |
| 09G2S-12 | GOST (Russia/CIS) | Near | Category 12 = impact at −40 °C; low-alloy 09G2S exceeds S355J2 toughness but yield is 325–345 MPa. |
| IS 2062 E350 C | IS (India) | Near | Yield 350 MPa, quality C = impact at −20 °C. |
| SM490B | JIS (Japan) | Near | Yield 325 MPa, Rm 490–610 MPa, 27 J at 0 °C (not −20 °C); SM490YB is closer on yield (365 MPa). |
| S355J2W | EN (European) | Functional | Same mechanical properties without the weathering alloying — use where the steel is painted or galvanized. |
| S355MC | EN (European) | Functional | Normalized/as-rolled structural steel of the same yield; heavier chemistry (C ≤ 0.22), larger bend radii, chosen for plate and sections rather than cold-formed parts. |
Identical = same composition and mechanical limits within rounding. Near = one limit differs (e.g. carbon max or impact temperature). Functional = interchangeable for most uses after an engineering check. Full cross-reference for S355J2 →
Old and superseded designations
| Old name | Standard | Note |
|---|---|---|
| St52-3 N | DIN 17100 | Normalized St52-3; the direct predecessor. |
| Fe510D / Fe510D1 | EN 10025:1990 | |
| S355J2G3 | EN 10025:1993 | G3 = normalized delivery; merged into S355J2 in the 2004 edition. |
| 50D | BS 4360 | |
| E36-4 | NF A 35-501 |
Product forms and tolerance standards
Product forms: hot-rolled plate (most common, usually +N), hot-rolled coil, sections, bar and flat, hollow sections (S355J2H).
Dimensional tolerances: plate: EN 10029 class A (thickness), flatness class N; coil/sheet: EN 10051; sections: EN 10034.
Key property values
S355J2 yield strength
Minimum ReH 355 MPa (51.5 ksi) to 16 mm, 345 MPa to 40 mm, 335 MPa to 63 mm, 325 MPa to 80 mm, 315 MPa to 100 mm, 295 MPa to 150 mm and 275 MPa up to 250 mm.
S355J2 tensile strength
Rm 470–630 MPa (68–91 ksi) to 100 mm, 450–600 MPa from 100 to 250 mm.
S355J2 hardness
Not a standard requirement; normalized plate is typically 150–190 HB. Flame-cut edges can locally reach 250–300 HV and should be ground before cold bending.
Impact energy
27 J at −20 °C (longitudinal, full-size specimen). Transverse values, if ordered, are typically ≥ 20 J.
Weldability
Good weldability with E46 / G46 consumables. CEV up to 0.45–0.47 %; for t > 25 mm calculate preheat with EN 1011-2 (typically 50–125 °C). Low-hydrogen consumables (≤ 5 ml/100 g) are standard for cranes and bridges. PWHT not usually required; if performed, 550–600 °C.
Machining, forming and heat treatment
Machines like S355JR (index ≈ 60 %). Cold bending of +N plate: minimum radius 1.5–3 t transverse depending on thickness (EN 10025-2 Table 7). Hot forming 950–1100 °C followed by re-normalizing 880–920 °C to restore J2 toughness. Flame cutting: preheat 100 °C above 30 mm to avoid edge cracking.
Typical applications
- Crane girders, booms and structural parts of lifting equipment
- Bridge plate girders and orthotropic decks (+N)
- Machinery frames and earthmoving-equipment structures
- Wind-turbine tower shells
- Heavy plate for shipbuilding secondary structure and offshore modules
- Hollow sections S355J2H for exposed architectural steelwork
S355J2 compared with related grades
Frequently asked questions
What does J2 mean in S355J2?
J = 27 J minimum Charpy V-notch energy, 2 = test temperature −20 °C. Compare JR (+20 °C), J0 (0 °C) and K2 (40 J at −20 °C).
Is S355J2 the same as S355J2+N?
+N is the delivery condition (normalized or normalizing-rolled). S355J2 without a suffix may be supplied +AR, +N or +M at the mill's choice; specify +N when you need guaranteed toughness through thickness.
What is the difference between S355J2 and S355N?
S355N (EN 10025-3) is a normalized fine-grain steel with Nb/V/Ti additions and a guaranteed 40 J at −20 °C (S355NL: 27 J at −50 °C). It is used where toughness matters more than cost.
What is the ASTM equivalent of S355J2?
ASTM A572 Grade 50 with supplementary requirement S5 (Charpy), or A709 Grade 50 for bridges. Neither is identical — yield is 345 MPa and Charpy values are by agreement.
Can S355J2 be used at −30 °C?
The guarantee is at −20 °C. For −30 °C and below, order S355K2 or S355N/NL (EN 10025-3) or S355ML (EN 10025-4).
Related grades
Verified against EN 10025-2:2019; EN 10025-2:2019 Tables 2, 4, 7 and 8; EN 1011-2:2001. Last checked: September 2026.