S355NL vs S355J2+N Key Comparison

S355NL vs S355J2+N: Key Comparison

S355NL vs S355J2+N is a critical comparison for selecting structural steels under the EN 10025 standard. S355NL, specified under EN 10025-3, is a normalized fine-grain steel optimized for low-temperature toughness, while S355J2+N, under EN 10025-2, is a normalized non-alloy steel for general use. This article compares their chemical composition, mechanical properties, weldability, and applications to highlight the S355J2 N vs S355NL differences, addressing core keywords s355nl vs s355j2 n and s355j2 n vs s355nl. For more details, visit our EN 10025-3 S355NL normalized structural steel plate.

Overview of S355NL and S355J2+N

S355NL (EN 10025-3)

S355NL is a fine-grain structural steel, normalized or normalized rolled, with:

• S: Structural steel.
• 355: Minimum yield strength of 355 MPa (≤16 mm).
• NL: Normalized, with impact toughness tested at -50°C for low-temperature performance.

It’s ideal for cold climates, such as offshore platforms and arctic bridges.

S355J2+N (EN 10025-2)

S355J2+N is a non-alloy structural steel, normalized or normalized rolled, with:

• S: Structural steel.
• 355: Minimum yield strength of 355 MPa (≤16 mm).
• J2: Impact toughness tested at -20°C.
• +N: Normalized condition, improving toughness over hot-rolled variants.

S355J2+N is cost-effective for general construction in moderate climates.

Chemical Composition Comparison

The S355NL vs S355J2+N comparison reveals differences in composition affecting toughness and weldability.

Carbon Equivalent (CEV):

• S355NL: ≤0.43% (≤63 mm).
• S355J2+N: ≤0.45% (≤40 mm).

The S355J2 N vs S355NL composition shows S355NL’s lower carbon (0.18% vs 0.20%), sulfur (0.015% vs 0.025%), and grain-refining elements (Al, Nb, V) enhance toughness and weldability, while S355J2+N’s simpler composition reduces costs.

Mechanical Properties Comparison

The S355NL vs S355J2+N mechanical properties differ primarily in toughness and testing conditions.

Strength: Both grades share identical yield (355 MPa) and tensile strengths (470-630 MPa) for similar thicknesses, ensuring comparable load-bearing capacity.
Toughness: The key S355J2 N vs S355NL difference is toughness. S355NL’s -50°C impact testing (≥27 J) suits sub-zero climates, while S355J2+N’s -20°C testing is adequate for milder conditions.
Thickness Range: S355NL supports up to 250 mm with robust low-temperature properties; S355J2+N up to 250 mm but with less cold performance.

Welding and Heat Treatment

• S355NL: CEV ≤0.43% ensures excellent weldability with GMAW or SAW (EN 1011-2). Preheating (100-150°C) for >20 mm; PWHT (550-650°C) optional. Consumables: ER70S-6 (GMAW), EM12K flux with EH14 wire (SAW).
• S355J2+N: CEV ≤0.45% supports welding but may require slightly more preheating (>25 mm) due to higher sulfur. Same consumables apply.

The S355NL vs S355J2+N welding difference favors S355NL for reduced weld imperfections due to its fine-grain structure and lower CEV.

Applications

• S355NL:
  • Offshore platforms in cold marine environments.
  • Wind towers in sub-zero climates.
  • Bridges and cranes in northern regions.
    Its -50°C toughness ensures reliability in extreme cold. See EN 10025-3 S355NL normalized structural steel plate.
• S355J2+N:
  • Building frameworks in temperate climates.
  • Bridges and machinery in moderate conditions.
  • General fabrication where cost is a priority.

The S355J2 N vs S355NL application difference highlights S355NL’s suitability for cold environments and S355J2+N’s affordability for standard conditions.

Equivalent Grades

• S355NL: ASTM A633 Grade E, Q345E (China), TStE 355 (DIN).
• S355J2+N: ASTM A572 Grade 50, Q345B (China), SM490B (JIS).

See EN 10025-3 S420NL normalized structural steel plate.

Why Choose Gangsteel?

Gangsteel supplies both grades:

• Inventory: Extensive stock in China.
• Sizes: Thickness 6–250 mm, widths 2000/2500/3000 mm, lengths up to 12,000 mm.
• Delivery: 7-30 days globally.
• Certifications: EN 10204 3.1/3.2, UT testing (EN 10160), ABS/LR/BV/DNV approvals.
• Processing: Cutting, welding, bending.

Contact us for EN 10025-3 S355NL normalized structural steel plate.

FAQ

What is the main difference in S355NL vs S355J2+N?
S355NL is a fine-grain steel under EN 10025-3, tested at -50°C for sub-zero climates like arctic offshore platforms, with lower CEV (≤0.43%) for better weldability. S355J2+N, under EN 10025-2, is a non-alloy normalized steel tested at -20°C, suitable for temperate general construction, with slightly higher CEV (≤0.45%).

How does toughness differ in S355J2 N vs S355NL?
S355NL ensures ≥27 J at -50°C, ideal for cold environments like northern bridges, while S355J2+N’s ≥27 J at -20°C suits milder climates, limiting its use in sub-zero conditions.

Which is better for cold climates in S355NL vs S355J2+N?
S355NL is superior for cold climates due to its -50°C impact toughness, ensuring reliability in arctic or offshore applications, whereas S355J2+N is limited to -20°C, better for temperate regions.

Are S355J2 N vs S355NLstrengths similar?
Yes, both have identical yield strength (355 MPa) and tensile strength (470-630 MPa) for similar thicknesses, providing comparable load-bearing capacity for structural designs like bridges or frameworks.

Which is more weldable in S355NL vs S355J2+N?
S355NL’s lower CEV (≤0.43% vs ≤0.45%) and fine-grain structure reduce preheating needs (100-150°C vs >25 mm for S355J2+N), minimizing weld imperfections in applications like wind towers.

What are applications of S355J2 N vs S355NL?
S355NL is used in cold-climate offshore platforms, wind towers, and bridges due to its -50°C toughness. S355J2+N suits temperate building frameworks, bridges, and machinery, offering cost savings for less extreme conditions.

Can S355J2+N replace S355NL?
S355J2+N can replace S355NL in temperate climates above -20°C, but for sub-zero environments like arctic regions, S355NL’s -50°C toughness is essential, making it irreplaceable.

Explore related grades like EN 10025-3 S275N normalized structural steel plate.