EN 10025-2 S355JR Steel Specification: What Buyers Should Know

S355JR is the workhorse of European structural steel. Specified under EN 10025-2, this hot-rolled non-alloy grade offers a minimum yield strength of 355 MPa, excellent weldability, and wide availability in plates, sections, and bars. For buyers exporting to EU member states, EEA projects, or spec-driven Middle East developments, understanding the S355JR specification is essential to avoid certification gaps and delivery disputes. This article covers chemistry, mechanicals, sub-grades, testing, and equivalent standards.

1. Chemical Composition (Ladle Analysis)

Element	Max % (≤ 30 mm)	Max % (> 30 mm)
C	0.24	0.24
Si	0.55	0.55
Mn	1.60	1.60
P	0.035	0.035
S	0.035	0.035
Cu	0.55	0.55
N	0.012	0.012

Carbon equivalent (CEV) is limited to 0.47 max for thicknesses up to 30 mm and 0.49 for thicker material, ensuring good weldability without preheat in most ambient conditions.

2. Mechanical Properties at Room Temperature

Property	Value (≤ 16 mm)
Yield Strength (ReH)	≥ 355 MPa
Tensile Strength (Rm)	470 – 630 MPa
Elongation (A, Lo = 5.65√So)	≥ 22%
Impact Energy (Charpy V, +20°C)	≥ 27 J (Longitudinal)

Note that the “JR” suffix indicates a minimum 27 J impact test at +20°C. For colder climates, specify J0 (0°C) or J2 (-20°C) sub-grades.

3. Sub-Grades: JR, J0, J2, and K2

• S355JR: Room-temperature impact (+20°C), standard structural use.
• S355J0: 0°C impact, suitable for mildly cold environments.
• S355J2: -20°C impact, required for bridges and offshore in Northern Europe.
• S355K2: -20°C impact with longitudinal testing, premium grade for critical infrastructure.

4. Delivery Conditions and Tolerances

EN 10025-2 S355JR is supplied in the as-rolled (+AR) or normalized (+N) condition. Plates are typically governed by EN 10029 for thickness tolerance Class A or B, while long products follow EN 10034 (sections) or EN 10060 (round bars). When ordering, always state:

• Standard and steel grade (EN 10025-2 S355JR)
• Product form and dimensions
• Delivery condition (+AR or +N)
• Inspection document type (EN 10204 3.1 or 3.2)
• Impact test temperature if deviating from JR

5. Equivalent Standards Worldwide

Standard	Equivalent Grade
ASTM A572	Grade 50
JIS G3106	SM490A / SM490B
GB/T 1591	Q355B
DIN 17100	St 52-3 (legacy)
ISO 630	E355

6. Typical Applications

• Commercial and residential building frames
• Bridge girders and highway infrastructure
• Wind turbine towers and substation structures
• Crane booms and material handling equipment
• Pressure vessels and storage tanks (when combined with PED compliance)

7. FAQ

Is S355JR weldable without preheat?

For thicknesses up to 30 mm and ambient temperatures above 0°C, preheat is generally not required. Above 30 mm or in sub-zero welding conditions, follow EN 1011-2 preheat tables.

Can S355JR be used for pressure equipment?

Only if the material complies with PED 2014/68/EU and the specific design code (e.g., EN 13445). Standard S355JR plate may require additional testing for elevated-temperature properties.

What is the difference between S355JR and S355J2?

Only the impact test temperature: JR at +20°C, J2 at -20°C. Chemistry and strength are identical. For outdoor structures in cold climates, J2 is mandatory in most EU countries.

8. Conclusion

EN 10025-2 S355JR is the default choice for structural steel buyers serving European and Middle Eastern markets. Its predictable chemistry, wide size range, and global mill availability make procurement straightforward—provided you specify the correct sub-grade, delivery condition, and inspection document. At Huaxia-Steel, we stock S355JR plate from 6 mm to 150 mm and structural sections in +AR and +N conditions, all with EN 10204 3.1 certification.