S355NL vs S355MC Structural Steel

S355NL vs S355MC: Structural Steel

S355MC vs S355NL is a key 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 S355MC, under EN 10025-4, is a thermomechanically rolled (TMCP) steel designed for high strength and formability in thinner sections. This article compares their chemical composition, mechanical properties, weldability, and applications to determine their suitability, addressing the core keyword s355mc vs s355nl. For more details, visit our EN 10025-3 S355NL normalized structural steel plate.

Overview of S355NL and S355MC

S355NL (EN 10025-3)

S355NL is a normalized or normalized rolled fine-grain structural steel 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, due to its robust toughness across a wide thickness range.

S355MC (EN 10025-4)

S355MC is a thermomechanically rolled (TMCP) structural steel with:

• S: Structural steel.
• 355: Minimum yield strength of 355 MPa (≤16 mm).
• MC: Thermomechanically rolled, optimized for cold forming and high strength in thinner sections.

S355MC is designed for applications requiring formability, such as automotive components and structural profiles, with testing typically at -20°C.

Chemical Composition Comparison

The S355MC vs S355NL comparison shows differences in composition that affect toughness and formability.

Carbon Equivalent (CEV):

• S355NL: ≤0.43% (≤63 mm).
• S355MC: ≤0.39% (≤40 mm), lower due to reduced carbon and optimized TMCP, enhancing weldability and formability.

The S355MC vs S355NL composition shows S355MC’s lower carbon (0.12% vs 0.18%) and higher microalloying (Nb, V, Ti) improve formability, while S355NL’s composition supports toughness in thicker sections.

Mechanical Properties Comparison

The S355MC vs S355NL mechanical properties differ in toughness and thickness range.

Strength: Both grades have similar yield strength (355 MPa at ≤16 mm), but S355NL’s tensile strength (470-630 MPa) is higher than S355MC’s (430-550 MPa), making it stronger for thicker sections.
Toughness: S355NL is tested at -50°C (≥27 J), ideal for sub-zero climates, while S355MC’s -20°C testing (≥40 J) suits milder conditions and prioritizes formability.
Thickness Range: S355NL supports up to 250 mm; S355MC is limited to thinner sections (typically ≤16 mm, max 40 mm), optimized for cold forming.

Welding and Heat Treatment

• S355NL: CEV ≤0.43% supports GMAW or SAW (EN 1011-2). Preheating (100-150°C) for >20 mm; PWHT optional (550-650°C). Consumables: ER70S-6 (GMAW), EM12K flux with EH14 wire (SAW).
• S355MC: Lower CEV (≤0.39%) enhances weldability, requiring less preheating (50-100°C for >10 mm). Same consumables apply.

The S355MC vs S355NL welding comparison favors S355MC for thinner sections due to lower CEV, but S355NL is more versatile for thicker plates.

Applications

• S355NL:
  • Offshore platforms in cold marine environments (e.g., North Sea).
  • Wind turbine towers in sub-zero climates.
  • Bridges and cranes in northern regions.
    Its -50°C toughness and wide thickness range (up to 250 mm) ensure reliability in heavy-duty, cold applications. See EN 10025-3 S355NL normalized structural steel plate.
• S355MC:
  • Automotive components (e.g., chassis, structural profiles).
  • Cold-formed sections for lightweight structures.
  • Thin-walled construction in temperate climates.
    Its TMCP process enhances formability for thinner sections (≤16 mm).

The S355MC vs S355NL application difference highlights S355NL’s suitability for cold, heavy structures and S355MC’s advantage in formable, lightweight components.

Which is Better: S355NL or S355MC?

• Choose S355NLfor:
  • Thick sections (up to 250 mm) requiring -50°C toughness.
  • Heavy-duty structures in cold climates (offshore, arctic bridges).
  • Applications needing higher tensile strength (470-630 MPa).
• Choose S355MCfor:
  • Thin sections (≤16 mm) requiring cold forming.
  • Automotive or lightweight structural components.
  • Cost-effective fabrication with lower preheating needs.

The S355MC vs S355NL choice depends on thickness, temperature, and formability requirements. S355NL excels in cold, heavy applications; S355MC in formable, thinner structures.

Equivalent Grades

• S355NL: ASTM A633 Grade E, Q345E (China), TStE 355 (DIN).
• S355MC: ASTM A1011 HSLAS-F Grade 50, Q355MC (China).

See EN 10025-3 S420NL normalized structural steel plate.

Why Choose Gangsteel?

Gangsteel supplies both grades:

• Inventory: Extensive stock in China.
• Sizes: S355NL (6–250 mm), S355MC (1.5–16 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, forming (S355MC).

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

FAQ

What is the main difference in S355MC vs S355NL?
S355NL is normalized, tested at -50°C for cold climates and thicker sections (up to 250 mm) with tensile strength 470-630 MPa. S355MC is thermomechanically rolled, tested at -20°C, optimized for cold forming in thinner sections (≤16 mm) with tensile strength 430-550 MPa.

Which is better for cold climates in S355MC vs S355NL?
S355NL is better for cold climates, with guaranteed ≥27 J impact toughness at -50°C, ideal for arctic offshore platforms and bridges. S355MC’s -20°C testing (≥40 J) is less suited for extreme cold but sufficient for temperate regions.

How does weldability compare in S355MC vs S355NL?
S355MC’s lower CEV (≤0.39% vs ≤0.43%) requires less preheating (50-100°C vs 100-150°C for >10 mm), making it more cost-effective for welding thinner sections. S355NL is equally weldable for thicker plates, using GMAW/SAW with ER70S-6 consumables.

What are applications of S355MC vs S355NL?
S355NL is used in cold-climate offshore platforms, wind towers, and bridges (6–250 mm). S355MC is used in automotive chassis, cold-formed profiles, and lightweight structures (≤16 mm) in temperate climates, leveraging its formability.

Which is more formable in S355MC vs S355NL?
S355MC is more formable due to its TMCP process and lower carbon (0.12% vs 0.18%), making it ideal for cold-formed components like structural profiles. S355NL prioritizes toughness over formability for thicker structures.

Can S355MC replace S355NL?
S355MC can replace S355NL in thinner sections (≤16 mm) for temperate climates where cold forming is needed, but not in cold climates or thicker sections due to S355NL’s superior -50°C toughness and wider thickness range.

Explore related grades like EN 10025-3 S355N normalized structural steel plate.