Steel S355J2G3
ASTM A572 Grade 50 · EN 1.0570, S355J2 · GB Q355B
S355J2G3 is the older EN designation (1.0570) for a normalized structural carbon-manganese steel, now superseded by S355J2 and comparable to A572 Grade 50, Q355B and SM490A.
Reference datasheet — S355J2G3 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the N condition
S355J2G3 tempers and conditions
S355J2G3 is supplied in 5 conditions, soft to hard. N is the default FabDigit quotes; the values on this page are for it.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
as-rolled (hot rolled, no specified delivery condition) | Cheapest hot-rolled sections and plate where mill chooses delivery condition (S355J2+AR / J2G4); slightly coarser grain and lower typical toughness than +N. | 380 | 520 | 23 | 150 HB | 10 % IACS |
NDefault Normalized | Standard stock condition: fine ferrite-pearlite grain, guaranteed 27 J at −20 °C, best choice for welded structures and thicker plate. | 390 | 520 | 24 | 150 HB | — |
Thermomechanically controlled processed | TMCP plate with lower carbon equivalent: same strength with better low-temperature toughness and easier welding of thick sections. | 400 | 510 | 25 | 155 HB | 10 % IACS |
Quenched and tempered | Occasionally supplied for heavy forgings/bars needing uniform through-thickness properties and improved sub-zero toughness. | 430 | 570 | 22 | 175 HB | 10 % IACS |
cold drawn / cold finished bar | Cold-drawn bar for shafts and machined parts: higher yield and better surface/tolerance, at the cost of ductility and residual stress. | 470 | 600 | 12 | 185 HB | 10 % IACS |
What is S355J2G3?
S355J2G3 is the older EN designation (1.0570) for a normalized structural carbon-manganese steel, now superseded by S355J2 and comparable to A572 Grade 50, Q355B and SM490A. It is the default choice for welded construction and machine structures at 390 MPa yield, 520 MPa tensile, 24 % elongation and about 150 HB (80 HRB), and is available as-rolled, normalized, thermomechanically rolled, cold-formed or quenched and tempered. Weldability is 88/100 and formability moderate (68/100); there is no corrosion resistance and no elevated-temperature qualification, so use P355N-family plate for pressure equipment. S355J2G3 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). S355J2G3 has a yield strength of 390 MPa (56.6 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 64% of steel grades. Elongation at break is 24% and the elastic modulus is 210 GPa (30.5 Msi).
What is S355J2G3 used for?
- structural beams
- bridge girders
- general fabrication
- machinery frames
Advantages
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
- Readily welded — 88/100, better than 87% of steel grades
- High electrical conductivity — 10 % IACS, better than 83% of steel grades
- Forms and bends easily — 68/100, better than 83% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
S355J2G3 properties
Typical room-temperature values for S355J2G3-N; bars are the position among steel grades.
Physical3
S355J2G3 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
S355J2G3 has a yield strength of 390 MPa (56.6 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 64% of steel grades. Elongation at break is 24% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
S355J2G3 is rated for continuous service to 400°C (752 °F). It conducts heat at 45 W/m·K (26 BTU/hr·ft·°F), better than 66% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
S355J2G3 conducts electricity at 10 % IACS, better than 83% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of S355J2G3 takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability8
S355J2G3's machinability is good (60/100, better than 83% of steel grades); weldability excellent (88/100); formability good (68/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. S355J2G3 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with S355J2G3
Is S355J2G3 easy to machine?
Machines like a medium-carbon steel — use carbide at ~120–180 m/min with generous feed; gummy chips at low hardness, so avoid dull edges and consider stress relief before finish cuts on cold-drawn bar.
Can S355J2G3 be welded?
Excellent weldability by SMAW/GMAW/SAW with matching low-hydrogen consumables (E7018 / G46); preheat 100–150 °C for thickness >30 mm or high restraint per EN 1011-2.
Can S355J2G3 be formed, bent or molded?
Good cold bending (minimum bend radius ≈1–2.5 t depending on thickness/orientation); hot forming 900–1050 °C followed by normalizing to restore J2 toughness.
S355J2G3 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| C≤0.20 for t ≤ 30 mm; ≤0.22 thicker (EN 10025-2) | ≤ 0.2 | 0.17 |
| Si | ≤ 0.55 | 0.25 |
| Mn | ≤ 1.6 | 1.4 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Nno limit if sufficient N-binding elements present | ≤ 0.01 | 0.01 |
| Cu | ≤ 0.55 | 0.2 |
| Nb+V+Timicro-alloying, optional | ≤ 0.15 | 0.03 |
| CEVcarbon equivalent, t ≤ 30 mm | ≤ 0.45 | 0.42 |
| Fe | balance |
What surface finishes work on S355J2G3?
No natural corrosion resistance — hot-dip galvanize (watch Si in the 0.03–0.12 % 'Sandelin' band), metallize or shot-blast to Sa 2½ and paint; phosphating suits fasteners and machined parts.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel S355J2G3 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
How much does S355J2G3 cost?
S355J2G3 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
S355J2G3 — frequently asked
What is S355J2G3 used for?
S355J2G3 is typically used for structural beams, bridge girders, general fabrication and machinery frames. In short: workhorse 355 MPa structural steel; superseded name for S355J2; not for pressure equipment.
What is the yield strength of S355J2G3?
S355J2G3 has a typical yield strength of 390 MPa (56.6 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 64% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is S355J2G3 easy to machine?
Reasonably — machinability is rated good (60/100, better than 83% of steel grades). Machines like a medium-carbon steel — use carbide at ~120–180 m/min with generous feed; gummy chips at low hardness, so avoid dull edges and consider stress relief before finish cuts on cold-drawn bar.
Can S355J2G3 be welded?
Yes — weldability is rated excellent (88/100). Excellent weldability by SMAW/GMAW/SAW with matching low-hydrogen consumables (E7018 / G46); preheat 100–150 °C for thickness >30 mm or high restraint per EN 1011-2.
What surface finishes work on S355J2G3?
No natural corrosion resistance — hot-dip galvanize (watch Si in the 0.03–0.12 % 'Sandelin' band), metallize or shot-blast to Sa 2½ and paint; phosphating suits fasteners and machined parts.
Can S355J2G3 be formed, bent or molded?
Good cold bending (minimum bend radius ≈1–2.5 t depending on thickness/orientation); hot forming 900–1050 °C followed by normalizing to restore J2 toughness.
What is the maximum service temperature of S355J2G3?
S355J2G3 is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between S355J2G3-N and S355J2G3-C?
N is the default condition — standard stock condition: fine ferrite-pearlite grain, guaranteed 27 J at −20 °C, best choice for welded structures and thicker plate. C: cold-drawn bar for shafts and machined parts: higher yield and better surface/tolerance, at the cost of ductility and residual stress. Yield strength is 390 MPa in N versus 470 MPa in C.
How much does S355J2G3 cost?
S355J2G3 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- EN 10025-2 Hot rolled products of structural steels — Non-alloy structural steels — CEN (2019)
- EN 10027-1/-2 designation systems for steels (1.0570) — CEN (2016)
- ASTM A572/A572M Grade 50 HSLA structural steel — ASTM (2021)
- EN 1993-1-1 / EN 1993-1-2 Eurocode 3 material properties — CEN (2005)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- EN 1011-2 Welding — recommendations for arc welding of ferritic steels — CEN (2001)
- worldsteel Life Cycle Inventory for steel products — World Steel Association (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.