EN 10025-3 Grade S420NL material specification properties

EN 10025-3 Grade S420NL Material Specification Properties

As a premier exporter and manufacturer of high-quality structural steel plates, Gangsteel specializes in producing EN 10025-3 compliant materials, including the versatile S420NL steel grade.

S420NL is a normalized fine-grain structural steel designed for welded constructions requiring enhanced toughness at low temperatures, down to -50°C.

Ideal for heavy-duty applications in bridges, cranes, and offshore structures, our S420NL plates are delivered in normalized or normalized rolled conditions to ensure superior weldability and impact resistance.

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

Overview of EN 10025-3 Grade S420NL

EN 10025-3 Grade S420NL is a high-strength low-alloy (HSLA) fine-grain structural steel specified in the European standard EN 10025-3:2019 for hot-rolled products of structural steels with technical delivery conditions for normalized/normalized rolled weldable fine grain structural steels. The designation "S420NL" breaks down as "S" for structural steel, "420" for a minimum yield strength of 420 MPa (for thicknesses ≤16 mm), and "NL" for normalized delivery with low-temperature impact testing at -50°C (27 J minimum longitudinal). This grade is optimized for environments demanding high ductility and resistance to brittle fracture in cold conditions, distinguishing it from milder variants like S355NL.

Gangsteel produces S420NL plates in thicknesses up to 250 mm, with precise control over chemical composition to meet CEV limits for optimal weldability. Our plates are rigorously tested to comply with international standards, ensuring reliability for global projects.

Chemical Composition of EN 10025-3 Grade S420NL

The chemical composition of S420NL is tightly controlled to achieve low carbon equivalent for weldability and microalloying for fine-grain structure (ladle analysis, max % unless noted).

*Note: For long products, P and S may be 0.005% higher. Al minimum ensures grain refinement if other N-binding elements are absent. Low P/S improve toughness; CEV ≤0.48 ensures weldability without preheating for thin sections.

Mechanical Properties of EN 10025-3 Grade S420NL

S420NL offers high yield strength and excellent low-temperature ductility, with properties varying by thickness (normalized condition, minimum values).

*Note: Elongation per Lo = 5.65 √So. Impact values increase at higher temperatures. These properties make S420NL ideal for cold-resistant structures.

Heat Treatment Guide for S420NL Steel

S420NL is supplied in normalized (+N) condition, involving heating to 880–920°C, soaking, and air cooling to refine grain structure.

• Preheating for Welding: Not required ≤50 mm; 100–150°C for thicker (CEV ≤0.48).
• PWHT: Optional 550–650°C stress-relief.
• Hot Forming: >850°C; re-normalize if <720°C.

Follow EN 1011-2. Gangsteel optimizes for minimal heat treatment.

Applications of S420NL Steel

• Heavy Engineering: Cranes, frameworks.
• Infrastructure: Bridges, offshore.
• Construction: Shipbuilding, vessels.

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Why Gangsteel for S420NL Steel?

With ISO-certified quality, Gangsteel delivers S420NL plates tailored to specifications, stocked for immediate export. Visit our en 10025 3 s420nl normalized structural steel plate page for details.

Summary

EN 10025-3 S420NL is a high-strength normalized fine-grain structural steel with 420 MPa yield, 520–680 MPa tensile, and 27 J impact at -50°C. Its controlled chemistry (CEV ≤ 0.48) and fine-grain structure make it ideal for welded structures in cold environments like bridges and offshore platforms. S420NL from Gangsteel ensures reliability for global projects.

FAQ

What is the difference between S420N and S420NL steel?

S420N provides impact testing down to -20°C (40 J longitudinal), while S420NL extends this to -50°C (27 J longitudinal). Both are normalized fine-grain steels under EN 10025-3, but S420NL is ideal for arctic or sub-zero conditions.

What are the maximum thicknesses available for S420NL plates?

Gangsteel supplies S420NL plates up to 250 mm thick, with mechanical properties adjusted for thicker sections to maintain structural integrity.

Is S420NL suitable for welding without preheating?

Yes, due to its low CEV (max 0.48), S420NL exhibits excellent weldability. Preheating is typically not required for thicknesses under 50 mm, but consult project specifications for optimal procedures.

What certifications does Gangsteel provide with S420NL plates?

All plates come with EN 10204 3.1 mill certificates, including chemical analysis, mechanical test results, and impact testing. We also offer third-party inspections like Lloyd's Register or DNV upon request.

Can S420NL be used in offshore structures?

Absolutely—its high toughness at -50°C and corrosion resistance (with proper coatings) make it a preferred material for offshore platforms, as per EN 10025-3 standards.