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EN10025-3 S420N: High-Strength Normalized Structural Steel

As a premier exporter and manufacturer of high-quality structural steel plates, Gangsteel specializes in producing EN10025-3 compliant materials, including the robust S420N steel grade.

S420N(also known as grade S420N or S420N steel grade) is a high-strength, low-alloy (HSLA), fine-grain normalized structural steel with 420 MPa minimum yield strength and excellent impact toughness at -20°C.

This S420N material is designed for heavy welded constructions such as bridges, offshore platforms, cranes, high-rise buildings, and pressure vessels.

Our EN 10025 3 S420N steel plates are delivered in normalized (+N) condition to ensure fine-grain microstructure, superior weldability, and consistent mechanical properties.

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


 

S420N Chemical Composition (Ladle Analysis, Max %)

The S420N chemical composition is carefully controlled to achieve high strength while maintaining weldability.

Element

C

Si

Mn

P

S

Cr

Mo

Ni

V

Nb

Ti

Al

Cu

N

CEV

Max

0.20

0.60

1.00–1.70

0.025

0.020

0.30

0.10

0.80

0.20

0.05

0.05

≥0.020

0.55

0.025

0.48

CEV = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15Al ≥ 0.020% ensures fine-grain refinement via AlN formation.


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S420N Mechanical Properties (Normalized, Min Values)

The S420N mechanical properties vary by thickness but guarantee high strength and ductility.

Thickness (mm)

Yield ReH (MPa)

Tensile Rm (MPa)

Elongation A (%)

Impact (Longitudinal)

Transverse

≤ 16

420

520–680

19

40 J at -20°C

27 J

16 < t ≤ 40

400

520–680

19

40 J at -20°C

27 J

40 < t ≤ 63

390

520–680

19

40 J at -20°C

27 J

63 < t ≤ 80

380

520–680

18

40 J at -20°C

27 J

80 < t ≤ 100

370

520–680

18

40 J at -20°C

27 J

100 < t ≤ 200

360

500–650

18

40 J at -20°C

27 J

200 < t ≤ 250

340

500–650

18

40 J at -20°C

27 J

Elongation per Lo = 5.65 √So. Test direction: transverse unless specified.


 

S420N vs S420NL: Key Differences

Feature

S420N

S420NL

Impact Temp

-20°C

-50°C

Impact Energy (Long.)

40 J

27 J

Best For

Moderate cold

Arctic/offshore

Price

Base

+10–15%

S420N NLrefers to S420NL — the low-temperature variant.


 

S420N Equivalent Grades

Standard

S420N Steel Grade Equivalent

ASTM

A572 Gr. 65

DIN 17102

TStE 420

JIS G 3106

SM570

GB/T 1591

Q420B

S420NC steel= Not valid — likely typo for S420N or S420MC (EN 10149-2).


 

S420N Steel Properties Summary

  • S420N steel properties: High yield (420 MPa), fine-grain, normalized, CEV ≤0.48
  • S420N steel specifications: EN10025-3, thickness 6–250 mm, normalized delivery
  • S420N steel vs S420NL: Same strength, S420NL tested at -50°C for extreme cold

 

Applications

  • Heavy Bridges
  • Offshore Platforms(non-arctic)
  • Cranes & Lifting Gear
  • High-Rise Columns
  • Pressure Vessels

 

Why Gangsteel for EN10025-3 S420N?

  • Mill-Direct Supply
  • Full Certification– EN 10204 3.1/3.2
  • Testing– UT, Z35, HIC
  • Stock– 6–250 mm
  • Global Export

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


Summary

EN10025-3 S420Nis a high-strength normalized fine-grain structural steel with 420 MPa yield, 520–680 MPa tensile, and 40 J impact at -20°C. It is the S420N steel grade of choice for heavy welded structures in moderate cold. For -50°C, use S420NL.


 

FAQ

What is EN10025-3 S420N?

EN10025-3 S420Nis a high-strength normalized weldable fine-grain structural steel with 420 MPa minimum yield strength (≤16 mm), 520–680 MPa tensile strength, and 40 J impact toughness at -20°C. It is part of EN 10025-3 standard for normalized steels, ensuring fine-grain structure through controlled rolling and heat treatment.

What is the chemical composition of S420N?

The S420N chemical composition includes max 0.20% C, 1.00–1.70% Mn, 0.025% P, 0.020% S, and CEV ≤ 0.48, with grain refiners like Al ≥ 0.020%, Nb ≤ 0.05%, and V ≤ 0.20%. This balance provides high strength, low brittleness, and excellent weldability.

What are the mechanical properties of S420N?

S420N mechanical propertiesinclude:

  • Yield strength: 420 MPa (≤16 mm) down to 340 MPa (200–250 mm)
  • Tensile strength: 520–680 MPa (≤100 mm), 500–650 MPa (>100 mm)
  • Elongation: 19% (≤63 mm), 18% (>63 mm)
  • Impact: 40 J longitudinal / 27 J transverse at -20°C

All values in normalized condition.

What is the difference between S420N and S420NL?

S420N vs S420NL:

  • Same yield (420 MPa), tensile, and chemistry
  • S420N: Impact tested at -20°C (40 J long.)
  • S420NL: Impact tested at -50°C (27 J long.)

S420N NL= S420NL — use for arctic/offshore.

What is the equivalent of S420N steel?

S420N steel grade equivalent:

  • ASTM: A572 Gr. 65
  • DIN: TStE 420
  • JIS: SM570
  • GB: Q420B

All require normalized delivery for equivalence.

Is S420NC a valid grade?

No, S420NC steel is not defined in EN10025-3. Likely a typo for S420N, S420NL, or S420MC (EN 10149-2 thermomechanical steel).

 

 

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