S355J2G3 forgings
Open-die forged bars, seamless rolled rings, blocks, discs and shafts in S355J2G3 / 1.0570 normalized structural steel, manufactured to EN 10250-2 and supplied with EN 10204 3.1 material certificates.
- Material number
- 1.0570
- Current designation
- S355J2+NEN 10025-2:2004, no. 1.0577
- Forging standard
- EN 10250-2Non-alloy quality steels
- Delivery condition
- +NNormalized
- Min. yield, t ≤ 100 mm
- 315 MPa
- Impact toughness
- 27 Jat −20 °C, Charpy V-notch
Also written as S355J2 G3, S355 J2G3 and 1.0570. The spelling S335J2G3 appears on many supplier sites. It is a typing error for this same grade.
Summary
S355J2G3 is a non-alloy quality structural steel listed in EN 10025:1993 under material number 1.0570. EN 10025-2:2004 renamed it S355J2+N for flat products and S355J2 for long products. In the designation, S stands for structural steel, 355 is the minimum yield strength in MPa, J2 requires 27 J Charpy V-notch impact energy at −20 °C, and G3 means the steel is delivered normalized, now written as +N.
For forgings the controlling specification is EN 10250-2:2000. It sets a minimum upper yield strength of 315 MPa and a minimum tensile strength of 490 MPa up to 100 mm nominal thickness. Between 250 mm and 500 mm those figures fall to 265 MPa and 450 MPa.
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory in Jiangyin, Jiangsu Province, China. We forge S355J2G3 round bar, seamless rolled rings, blocks, discs, hollow bars, sleeves, gear shafts and pinion shafts to customer drawings. Send enquiries to sales@steelforgepieces.com or call +86 189 2135 9659.
What is S355J2G3 steel?
S355J2G3 is one of the weldable fine-grain structural steels. It suits work that needs moderate strength, reliable toughness below zero, and easy fabrication. It is a non-alloy quality steel. The chromium, molybdenum and nickel figures in the table below are residual limits left over from the melt rather than deliberate additions, and EN 10250-2 caps their total at 0.48 %.
The name is old. EN 10025:1993 used JR, J0 and J2 for impact class, followed by G1 to G4 for deoxidation and delivery condition. EN 10025-2:2004 dropped the G suffix and moved delivery condition to a separate symbol, so S355J2G3 became S355J2+N. Plenty of drawings, mill certificates and purchase specifications written before 2004 still call for S355J2G3, and many of those plants are still running. Jiangyin Jiangnan Metal quotes and certifies against the old name whenever a customer asks for it.
What the designation means
| Symbol | Meaning | Requirement |
|---|---|---|
| S | Structural steel | Steel for general structural use |
| 355 | Minimum yield strength | 355 MPa for thin sections; reduces with thickness |
| J2 | Impact energy class | Min. 27 J at −20 °C, Charpy V-notch, longitudinal, average of 3 |
| G3 | Delivery condition | Normalized or normalizing rolled (= +N) |
Chemical composition of S355J2G3
The chemical composition of S355J2G3 (1.0570) for open-die forgings is specified in EN 10250-2:2000. All figures are ladle analysis in mass percent.
| C | Si | Mn | Ni | P | S | Cr | Mo | Al | Cr + Mo + Ni |
|---|---|---|---|---|---|---|---|---|---|
| max 0.22 | max 0.55 | max 1.60 | max 0.30 | max 0.035 | max 0.035 | max 0.30 | max 0.08 | min 0.020 | max 0.48 |
| For forgings with an equivalent diameter or thickness greater than 100 mm, the carbon content shall be agreed between purchaser and supplier. Minimum 0.020 % aluminium provides the grain-refining nitrogen fix. | |||||||||
Carbon equivalent
EN 10025-2 limits the carbon equivalent value (CEV, IIW formula) for S355J2 to about 0.45 up to 30 mm, 0.47 from 30 to 150 mm, and 0.49 from 150 to 250 mm. CEV governs preheat and welding procedure, so Jiangyin Jiangnan Metal prints the calculated value on every S355J2G3 mill certificate. Tell us at enquiry stage if your welding procedure needs a tighter ceiling.
Mechanical properties of S355J2G3
Mechanical properties for S355J2G3 forgings change with section size. The table gives the minimum values EN 10250-2 requires in the normalized (+N) condition, tested at room temperature.
| Property | ≤ 100 mm | > 100 – 250 mm | > 250 – 500 mm |
|---|---|---|---|
| Rm — tensile strength, MPa | 490 | 450 | 450 |
| Re — upper yield strength, MPa | 315 | 275 | 265 |
| A — elongation at fracture, longitudinal, % | 20 | 18 | 18 |
| A — elongation at fracture, transverse, % | 12 | on enquiry | on enquiry |
| KV — Charpy V impact energy at −20 °C, J | 27 | 27 | 27 |
| Impact energy is the average of three specimens; a single value may fall to 70 % of the minimum. Transverse elongation above 100 mm is agreed at order stage. Sampling position and test temperature can be specified on your enquiry. | |||
S355J2G3 equivalent grades
The table lists the closest international grades. Only the EN entries are exact substitutions. The rest match on strength class but differ in chemistry limits, impact test temperature or delivery condition, so check them against the application before you substitute.
| Country / standard | Grade | Match |
|---|---|---|
| EN 10025-2:2004 (current) | S355J2+N — 1.0577 | Direct replacement |
| Germany — DIN 17100 | St 52-3 N — 1.0570 | Direct predecessor |
| United Kingdom — BS 4360 | 50 D | Close |
| Italy — UNI 7070 | Fe 510 D | Close |
| Spain — UNE 36080 | AE 355 D | Close |
| France — NF A35-501 | E 36-3 | Close |
| USA — ASTM A572 / A709 | Grade 50 | Approximate. Impact testing must be invoked separately. |
| Japan — JIS G3106 | SM490B / SM490YB | Approximate |
| China — GB/T 1591 | Q355D | Approximate |
| Russia — GOST 19281 | 09G2S | Approximate |
S355J2G3 forged products we manufacture
Jiangyin Jiangnan Metal forges S355J2G3 to drawing, to a client specification, or to a rough-machined envelope. The five groups below cover most of the S355J2G3 work that comes through the shop.
| Product family | Typical forms | Size range |
|---|---|---|
| Forged bars | Round bar, square bar, rectangular and flat bar, hexagonal bar | OD 80–1200 mm · length to 12 000 mm |
| Hollow forgings | Hollow bar, sleeves, bushings, cylinders, pipes, casings, shells, hubs, housings | OD 200–2500 mm · ID from 100 mm |
| Rings | Seamless rolled rings, forged rings, flanges, tyres, races | OD 300–4000 mm · height to 1000 mm |
| Blocks and discs | Blocks, discs, disks, plates, tube sheets | Up to 2500 mm diameter or diagonal |
| Shafts | Gear shafts, pinion shafts, spindles, stepped shafts, ring gears, gear wheels | OD 100–1500 mm · length to 12 000 mm |
| Single-piece weight 50 kg to 30 000 kg. We can leave machining allowance, rough-turn, bore, or finish-machine on CNC. Non-standard geometry is quoted from your drawing. | ||
Forging and heat treatment of S355J2G3
S355J2G3 forges easily. We work it from continuous-cast billet or from ingot on a hydraulic open-die press. Typical parameters, confirmed per order against section size and your specification:
- Forging temperature: heat evenly to 1150–1200 °C. Finish forging above 850 °C to avoid coarse grain and surface tearing.
- Reduction ratio: 3:1 minimum from billet to finished section as standard. Higher ratios where the specification calls for them.
- Normalizing (+N): 880–920 °C, soak by section, still air cool. Properties are guaranteed in this condition.
- Stress relief: 550–620 °C, furnace cool, where heavy machining or welding follows.
- Slow cooling: heavy sections cool in the furnace or in vermiculite to avoid hydrogen flaking.
S355J2G3 does not through-harden, so we do not quench and temper it. If the design needs more strength, 42CrMo4 and 34CrNiMo6 are the usual alternatives and Jiangyin Jiangnan Metal can price both on the same enquiry.
Welding
S355J2G3 welds well with all common arc processes. Thin sections often need no preheat. Above roughly 30 mm, on restrained joints, or when welding below 5 °C, use 100–150 °C preheat, rising with thickness and CEV. Use low-hydrogen consumables and control interpass temperature. Post-weld heat treatment at 550–600 °C suits heavy or highly restrained weldments.
Where S355J2G3 forgings are used
The −20 °C toughness guarantee is why S355J2G3 turns up so often in outdoor and marine structures in temperate and cold climates. Common applications for the forged product:
- Offshore platform nodes, pile caps and riser components
- Shipbuilding: stern frames, rudder stocks, bollards and deck fittings
- Bridge bearings, pins and anchorage forgings
- Crane and lifting equipment: sheave hubs, hooks, trunnions, slew rings
- Wind tower flanges and nacelle structural forgings
- Mining, earthmoving and forestry machinery: pins, bosses, pivot housings
- Pump and valve bodies, penstocks and hydro-power components
- Railway wagon and bogie forgings
- Pressure-vessel supports, saddles and non-pressure-retaining attachments
Testing, inspection and certification
Every S355J2G3 forging ships from Jiangyin Jiangnan Metal with an EN 10204 3.1 inspection certificate as standard. It shows heat number, chemical analysis, heat-treatment record and mechanical test results. EN 10204 3.2 with third-party endorsement is available on request.
- Chemical analysis by optical emission spectrometer, heat and product analysis
- Tensile testing to EN ISO 6892-1
- Charpy V-notch impact testing to EN ISO 148-1, at −20 °C or a lower specified temperature
- Brinell hardness to EN ISO 6506
- Ultrasonic testing to EN 10228-3 or ASTM A388, acceptance class agreed at order
- Magnetic particle inspection to EN 10228-1 and dye penetrant inspection
- Dimensional inspection against your drawing, with report
- Grain size and micro-structure examination where specified
Third-party witness inspection by SGS, BV, TÜV, Lloyd's Register or your own inspector can be arranged at any hold point. Tell us the hold points when you place the order.
What to include in an S355J2G3 enquiry
Send these eight things with your first message and we can quote price and lead time without going back and forth:
- Grade and any additional specification: S355J2G3, S355J2+N, or a client spec
- Drawing or finished dimensions, and whether the quoted size is forged or machined
- Quantity and whether repeat orders are expected
- Delivery condition required: normalized (+N), stress relieved, or as-forged
- Machining allowance, or "rough-turned / bored to drawing"
- NDT requirement and acceptance class
- Certification level: EN 10204 3.1 or 3.2, and any third-party inspection
- Destination port and required delivery date
Send to sales@steelforgepieces.com or call +86 189 2135 9659. Drawings in PDF, STEP, DWG or a clear photograph are all acceptable.
Frequently asked questions about S355J2G3
Is S355J2G3 the same as S355J2+N?
Yes, in practice. S355J2G3 is the EN 10025:1993 name and S355J2+N is the EN 10025-2:2004 name for the same normalized structural steel. The G3 suffix and the +N suffix both denote the normalized delivery condition. Material numbers differ slightly: 1.0570 for S355J2G3 and St 52-3 N, 1.0577 for S355J2.
What is the material number for S355J2G3?
S355J2G3 carries material number 1.0570, the same number used for DIN 17100 St 52-3 N. EN 10250-2:2000 lists the grade under 1.0570 for open-die forgings. The current EN 10025-2 grade S355J2 uses 1.0577.
What is the yield strength of S355J2G3?
In forged sections to EN 10250-2 the minimum upper yield strength is 315 MPa up to 100 mm nominal thickness, 275 MPa from 100 to 250 mm, and 265 MPa from 250 to 500 mm. The figure 355 in the grade name applies to thin rolled product, not to heavy forgings, so design values must be taken from the thickness-specific row.
What does J2 mean in S355J2G3?
J2 specifies the impact toughness class: a minimum Charpy V-notch impact energy of 27 J measured at −20 °C on longitudinal specimens, as the average of three tests. By comparison, JR is tested at +20 °C and J0 at 0 °C. J2 is why the grade is specified for cold-climate and offshore service.
What is the chemical composition of S355J2G3?
Per EN 10250-2:2000, ladle analysis in mass percent: carbon max 0.22, silicon max 0.55, manganese max 1.60, nickel max 0.30, phosphorus max 0.035, sulphur max 0.035, chromium max 0.30, molybdenum max 0.08, aluminium min 0.020, with the sum of chromium, molybdenum and nickel limited to 0.48. Above 100 mm the carbon content is agreed between purchaser and supplier.
Is S355J2G3 weldable?
Yes. S355J2G3 is designed for welded construction and suits all common arc processes. Sections above roughly 30 mm, restrained joints and cold-weather welding typically require 100–150 °C preheat with low-hydrogen consumables. Jiangyin Jiangnan Metal prints the calculated carbon equivalent on each mill certificate so your welding procedure can be qualified against the actual heat.
What is the ASTM equivalent of S355J2G3?
The nearest ASTM grade is A572 Grade 50 (or A709 Grade 50 for bridge work), which has a 345 MPa minimum yield. It is only an approximate match. ASTM A572 does not guarantee −20 °C impact energy by default, so a supplementary impact requirement must be invoked to reproduce the J2 property.
What forged shapes are available in S355J2G3?
Jiangyin Jiangnan Metal supplies S355J2G3 as forged round, square, flat and hexagonal bar; hollow bars, sleeves, bushings, cylinders and housings; seamless rolled rings and forged flanges; blocks, discs and plates; and gear shafts, pinion shafts, spindles and ring gears. Single-piece weights run from 50 kg to 30 tonnes.
Why is S355J2G3 sometimes written S335J2G3?
S335J2G3 is a typing error that started in an online steel database and has been copied across a lot of supplier sites. No such grade exists in EN 10025 or EN 10250. The correct designation is S355J2G3, where 355 is the minimum yield strength in MPa.
Who supplies S355J2G3 open-die forgings from China?
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, manufacturing S355J2G3 forged bars, rings, blocks, discs and shafts to customer drawings with EN 10204 3.1 certification. Contact sales@steelforgepieces.com or +86 189 2135 9659 for a quotation.
About the manufacturer
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China. Jiangyin sits in the Yangtze River delta forging cluster, about two hours from the ports of Shanghai and Ningbo. We forge bars, seamless rolled rings, blocks, discs, hollow sections and shafts in carbon, alloy, tool and stainless steels and in nickel alloys, for machine builders and for customers in energy, marine and heavy fabrication.
On S355J2G3 we quote from a drawing, from a client specification, or from a plain size list. We supply the grade under its old name as well as the current S355J2+N designation.
Related steel grades
Grades commonly cross-shopped with S355J2G3, all available as open-die forgings:
- 42CrMo4
- AISI 4140
- 1.7225
- 34CrNiMo6
- AISI 4340
- AISI 4130
- 18CrNiMo7-6
- 17CrNiMo6
- AISI 8620
- AISI 8630
- 17-4PH
- All carbon steel grades
Reference standards
- EN 10250-2:2000. Open die steel forgings for general engineering purposes, Part 2: Non-alloy quality and special steels. Source of the composition and mechanical properties on this page.
- EN 10025:1993. Hot rolled products of non-alloy structural steels. Original source of the S355J2G3 designation.
- EN 10025-2:2004. Technical delivery conditions for non-alloy structural steels. Replaced S355J2G3 with S355J2+N.
- EN 10027-1. Designation systems for steels.
- EN 10204. Types of inspection documents.
- DIN 17100. Withdrawn German standard, source of the St 52-3 N equivalence.
Prepared by the technical sales team at Jiangyin Jiangnan Metal Co., Ltd. Published . Last reviewed . Figures are taken from the standards listed above and are given for guidance. The agreed purchase specification governs any order.