s420n steel for en 10025-3

S420N Steel for EN 10025-3: High-Strength Normalized Structural Steel

As a premier exporter and manufacturer of high-quality structural steel plates, Gangsteel specializes in producing EN 10025-3 compliant materials, including the powerful S420N steel grade.

S420Nis a high-strength, low-alloy (HSLA), fine-grain normalized structural steel designed for heavy welded constructions that demand 420 MPa minimum yield strength and reliable toughness down to -20°C.

It is the go-to material for bridges, offshore platforms, cranes, high-rise buildings, and pressure vessels where strength-to-weight ratio and weldability are critical.

Our S420N plates are delivered in normalized (+N) condition, ensuring fine-grain microstructure, excellent ductility, and superior impact resistance.

For a comprehensive overview of our en 10025 3 normalized steel plate offerings, explore our full range.

What is S420N Steel? (EN 10025-3)

S420N(material number 1.8902) is defined in EN 10025-3:2019 – Hot rolled products of structural steels – Part 3: Technical delivery conditions for normalized/normalized rolled weldable fine grain structural steels.

Designation Breakdown:

S420NL= same strength, but impact tested at -50°C (27 J) — see comparison below.

Gangsteel produces S420N in thicknesses from 6 mm to 250 mm, with CEV ≤ 0.48 for optimal weldability.

Chemical Composition of S420N (Ladle Analysis, Max %)

CEV Formula: C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15 Low P & S = reduced risk of brittle fracture Al ≥ 0.020% = ensures fine-grain structure via AlN precipitation

Mechanical Properties of S420N (Normalized, Min Values)

Elongation based on Lo = 5.65 √So. Values apply to test pieces taken transverse to rolling direction unless specified.

S420N vs S420NL: Detailed Comparison

Use S420NLwhen sub-zero exposure is expected (e.g., North Sea platforms, Siberian pipelines). See our en 10025 3 s420nl normalized structural steel plate.

S420N Equivalent Grades (International)

S420NC= Not a standard grade — likely typo for S420N or S420MC (thermomechanical).

Applications of S420N Steel

Why Choose Gangsteel for S420N?

• Direct Mill Supply– Best pricing, no brokers
• Full Certification– EN 10204 3.1/3.2, UT, Z35, HIC
• Stock Ready– 6–250 mm, 2000–3500 mm width
• Global Logistics– FOB/CIF, DDP options
• Technical Support– WPS, welding advice, design optimization

Contact: admin@gangsteel.comProduct Page: en 10025 3 s420n normalized structural steel plate

Summary

EN 10025-3 S420Nis a high-strength normalized fine-grain structural steel with 420 MPa yield, 520–680 MPa tensile strength, and 40 J impact at -20°C. It is ideal for heavy welded structures in moderate cold environments. For -50°C service, use S420NL.

FAQ

What does “S420N” stand for in EN 10025-3?

S= Structural steel 420 = Minimum yield strength of 420 MPa (for thickness ≤ 16 mm) N = Delivery condition = Normalized (not as-rolled) Tested for 40 J impact energy at -20°C in the longitudinal direction. This ensures the steel maintains ductility and resists brittle fracture under load in cold weather (down to -20°C), making it suitable for bridges, cranes, and offshore structures in temperate to moderately cold climates.

What is the difference between S420N and S420NL?

The only difference is the impact test temperature and energy:

• S420N: 40 J (longitudinal) / 27 J (transverse) at -20°C
• S420NL: 27 J (longitudinal) / 16 J (transverse) at -50°C

All other properties (yield, tensile, elongation, chemistry) are identical. Choose S420NL when the structure will experience temperatures below -20°C, such as in arctic regions, offshore wind farms, or Siberian pipelines. S420N is sufficient and more cost-effective for moderate climates.

What is the ASTM equivalent of S420N?

ASTM A572 Grade 65is the closest equivalent:

• Yield strength: 450 MPa (slightly higher)
• Normalized delivery
• Comparable chemistry and weldability
• Impact testing can be specified to match -20°C

A572 Gr. 65 is widely used in the USA for high-strength structural applications like bridges and buildings.

Is S420NC a real steel grade?

No, S420NC does not exist in EN 10025-3 or any major standard. It is likely a typographical error for:

• S420N(normalized, EN 10025-3)
• S420NL(low-temp, EN 10025-3)
• S420MC(thermomechanical, EN 10149-2)

Always verify with mill certificates to avoid confusion.

Can S420N steel be welded without preheating?

Yes, preheating is generally not required for thicknesses up to 50 mm due to its low CEV ≤ 0.48 and controlled chemistry. For thicker sections (>50 mm) or high-restraint joints:

• Preheat to 100–150°C
• Use low-hydrogen electrodes (e.g., E9018, ER90S-G)
• Follow EN 1011-2 welding guidelines

Post-weld heat treatment (PWHT) is rarely needed unless specified for stress relief.

What are the main applications of S420N?

S420N is used where high strength + good toughness are needed:

• Bridges: Long-span girders, trusses
• Offshore platforms: Jackets, deck modules (non-arctic)
• Cranes: Booms, lattice structures
• High-rise buildings: Core columns, seismic bracing
• Pressure vessels: Thick-walled, high-stress

Its fine-grain structure ensures fatigue resistance and crack arrest properties.