EN 10025-2 — Hot-Rolled Structural Steels

EN 10025-2 covers hot-rolled products of non-alloy structural steels. The grade designation follows the pattern:

S {yield} {quality} {delivery condition}

Example: S355J2+N = Structural steel, min yield 355 MPa, quality J2 (impact at -20 °C), normalized (+N)

Grade Nomenclature

Symbol Meaning
S Structural steel
235-460 Minimum yield strength f_y for t ≤ 16 mm (MPa)
JR Impact energy 27J at +20 °C
J0 Impact energy 27J at 0 °C
J2 Impact energy 27J at -20 °C
K2 Impact energy 40J at -20 °C
+N Normalized or normalized rolled
+M Thermomechanically rolled
+AR As-rolled (no special delivery condition)
+QT Quenched and tempered (S420, S460, S500, S690)

Yield Strength f_y by Thickness Range — EN 1993-1-1 Table 3.1

Grade t ≤ 16 mm 16 < t ≤ 40 mm 40 < t ≤ 63 mm 63 < t ≤ 80 mm 80 < t ≤ 100 mm
S235 235 225 215 215 215
S275 275 265 255 245 235
S355 355 345 335 325 315
S420 420 400 390 370 360
S460 460 440 430 410 400

Note: Values are minimum yield strength f_y in MPa per EN 10025-2. For quenched and tempered grades (S460Q, S500Q, S620Q, S690Q), refer to EN 10025-6.

Ultimate Tensile Strength f_u by Thickness Range

Grade t ≤ 3 mm 3 < t ≤ 100 mm 100 < t ≤ 400 mm
S235 360-510 360-510 350-500
S275 430-580 410-560 400-540
S355 510-680 470-630 450-600
S420 520-680 520-680 500-660
S460 540-720 540-720 530-710

Chemical Composition Limits — EN 10025-2 Ladle Analysis (%)

Grade Quality C max Mn max Si max P max S max
S235 JR 0.17 1.40 — 0.035 0.035
S235 J0 0.17 1.40 — 0.030 0.030
S235 J2 0.17 1.40 — 0.025 0.025
S275 JR 0.21 1.50 — 0.035 0.035
S275 J0 0.18 1.50 — 0.030 0.030
S275 J2 0.18 1.50 — 0.025 0.025
S355 JR 0.24 1.60 0.55 0.035 0.035
S355 J0 0.20 1.60 0.55 0.030 0.030
S355 J2 0.20 1.60 0.55 0.025 0.025
S355 K2 0.20 1.60 0.55 0.025 0.025
S420 N/M 0.20 1.70 0.60 0.030 0.025
S460 N/M 0.20 1.70 0.60 0.030 0.025
S460 Q/QL1 0.20 1.70 0.80 0.025 0.015

Carbon Equivalent Value (CEV) — EN 10025-2

The carbon equivalent value (CEV) determines weldability. The IIW formula per EN 10025-1:

CEV = C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15

Grade Quality CEV max (t ≤ 40 mm) CEV max (40 < t ≤ 150 mm)
S235 JR 0.35 0.35
S275 JR/J0/J2 0.40 0.40
S355 JR/J0/J2 0.45 0.47
S355 K2 0.45 0.47
S420 N/M 0.48 0.50
S460 N/M 0.50 0.54
S460 Q 0.48 0.50

CEV ≤ 0.40: good weldability without preheat. CEV 0.40-0.47: moderate preheat may be required. CEV > 0.47: preheat and controlled heat input required per EN 1011-2.

Impact Energy (Charpy V-Notch) — EN 10025-2

Quality Test Temperature Min Impact Energy Application
JR +20 °C ≥ 27 J Indoor, unconditioned
J0 0 °C ≥ 27 J Outdoor, moderate climate
J2 -20 °C ≥ 27 J Outdoor, cold climate, exposed
K2 -20 °C ≥ 40 J Critical, fatigue, low temperature

For EN 1993-1-10 material selection against brittle fracture, the maximum permitted thickness for a given steel grade, quality, and stress level is given by Table 2.1. S355J2 is the default structural grade for most European building projects.

Elongation at Fracture — EN 10025-2 (%)

Grade L₀ = 5.65√S₀ (minimum) Typical Application Requirement
S235 26 General construction
S275 23 Secondary members
S355 22 Primary structural members
S420 19 High-strength, weight-critical
S460 17 High-strength, long spans

EN 10025 Product Standards by Category

Standard Product Type Grades
EN 10025-2 Hot-rolled non-alloy structural steels S235-S460 (JR to K2)
EN 10025-3 Normalized/normalized rolled fine-grain S275-S460 (N/NL)
EN 10025-4 Thermomechanical rolled fine-grain S275-S460 (M/ML)
EN 10025-5 Atmospheric corrosion resisting (weathering) S235W-S355W (J0-K2)
EN 10025-6 Quenched and tempered flat products S460Q-S690Q (Q/QL/QL1)

International Grade Equivalents

European to US (ASTM) Equivalents

EN 10025-2 ASTM A36 / A572 Nearest Match Notes
S235JR ASTM A36 Close match A36: f_y = 250 MPa (250 MPa min)
S275JR ASTM A572 Gr. 42 Approximate Gr. 42: f_y = 290 MPa
S355J0/J2 ASTM A572 Gr. 50 Close match Gr. 50: f_y = 345 MPa
S420N/M ASTM A572 Gr. 60 Approximate Gr. 60: f_y = 415 MPa
S460N/M/Q ASTM A572 Gr. 65 Close match Gr. 65: f_y = 450 MPa

European to Australian/New Zealand (AS/NZS) Equivalents

EN 10025-2 AS/NZS 3678 Match Quality
S235JR 250 Grade Close (250 MPa min)
S275JR 300 Grade Approximate
S355J0/J2 350 Grade Close match
S420N 400 Grade Close match

European to International (ISO) Equivalents

EN 10025-2 ISO 630
S235JR S235B
S275JR S275B
S355J0/J2 S355C/S355D
S420N S420N
S460N S460N

Material Selection for EN 1993-1-1 Design

Typical Grade Selection by Application

Application Recommended Grade Quality Reason
Simple secondary beams S235JR or S275JR JR Economy, minimal toughness
Primary beams and columns (internal) S355J0 J0 Standard for most buildings
Primary members (external) S355J2+N J2 Cold climate, exposed
Long-span trusses, bridges S355K2+N or S420M K2 Fatigue, higher toughness
High-rise columns, weight-critical S420M or S460M M High strength, reduced weight
Marine/offshore structures S355J2+N or S355K2 J2-K2 Corrosion, low temperature

Frequently Asked Questions

What is the most common structural steel grade in Europe?

S355J2+N is the default structural steel for most European building projects. It provides a minimum yield strength of 355 MPa for sections up to 16 mm thick, Charpy impact energy of 27 J at -20 °C, and normalised delivery condition for consistent properties. S355 offers a 35% strength increase over S275 with only a modest price premium (typically 5-10%), making it the cost-effective choice for primary structural members.

How do EN 10025 steel grades compare with ASTM and other international grades?

S355 is the closest European equivalent to ASTM A572 Grade 50 (f_y = 345 MPa / 50 ksi), which is the standard structural steel in North America. S275 approximates A572 Grade 42. S460 maps to A572 Grade 65. Key differences: EN grades specify impact energy at specific temperatures (JR, J0, J2, K2), while ASTM uses a Charpy requirement only when supplementary, and EN 10025 uses carbon equivalent values (CEV) for weldability assessment where ASTM uses carbon content limits.

What does the +N, +M, and +AR designation mean after the steel grade?

+N (normalized): The steel is heated and air-cooled to refine the grain structure, providing uniform properties and good toughness. +M (thermomechanically rolled): Controlled rolling and cooling produce fine-grain, high-strength steel without traditional normalizing, often with better weldability and lower CEV. +AR (as-rolled): No special heat treatment — properties vary more and toughness may be lower. For EN 1993-1-1 design, +N and +M are preferred; +AR is increasingly uncommon for structural applications.

What is the S355J2 vs S355J0 difference and when should I specify J2?

The difference is the Charpy impact test temperature: J0 requires 27 J at 0 °C; J2 requires 27 J at -20 °C. Specify J2 for external steelwork, cold climates, members in tension at low service temperatures, fatigue-loaded members, and any steel where the EN 1993-1-10 maximum thickness limits for J0 would restrict the design. The cost premium for J2 over J0 is typically 2-5%, making it cheap insurance for an unsuitable grade replacement.

Related Pages

Educational reference only. Grade properties per EN 10025-2:2019 and EN 1993-1-1:2005 Table 3.1. Chemical composition limits are ladle analysis values. Verify CEV against welding procedure specification. Always check mill certificates against the specified grade and quality. Results are PRELIMINARY — NOT FOR CONSTRUCTION without independent verification by a qualified structural engineer.

Design Resources

Calculator tools

Design guides

Reference pages