s275n vs s355n steel plate

s275n vs s355n steel plate

As a premier exporter and manufacturer of high-quality structural steel plates, Gangsteel specializes in producing EN 10025-3 compliant materials, including the versatile S275N and S355N steel plates.

S275N and S355N are both normalized fine-grain structural steel plates designed for welded constructions requiring enhanced toughness at low temperatures down to -20°C.

S275N offers a minimum yield strength of 275 MPa, while S355N provides higher strength at 355 MPa, making S355N more suitable for heavier loads than S275N.

Ideal for heavy-duty applications in bridges, cranes, and offshore structures, our S275N and S355N steel 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 S275N and S355N Steel Plates

S275N (material no. 1.0490) and S355N (1.0545) are weldable fine-grain steels under EN 10025-3 for normalized/normalized rolled delivery, with "N" indicating impact resistance at -20°C (47 J min longitudinal for S275N, 47 J for S355N). S355N's higher yield (355 MPa vs 275 MPa) allows thinner plates for the same load, but both share similar low-temperature toughness for moderate cold applications.

Gangsteel produces both in thicknesses up to 250 mm, with custom certifications.

Chemical Composition Comparison

Both have low-carbon profiles for weldability, but S355N allows slightly higher alloying for strength (ladle analysis, max % unless noted, ≤100 mm).

*Note: S355N's higher Mn and V boost strength; both maintain low P/S for toughness and CEV for weldability.

Mechanical Properties Comparison

Both are normalized for fine-grain structure, with S355N providing higher yield and tensile than S275N (minimum values for +N condition).

*Notes: Elongation per Lo = 5.65 √So. Transverse impact 31 J min at -20°C for both. S355N's higher strength allows thinner sections.

Heat Treatment and Welding Comparison

• Heat Treatment: Both normalized (+N: 880–920°C austenitize, air cool) for fine-grain.
• Welding: Low CEV (0.40/0.43), no preheat ≤40 mm; S355N may need more care for thicker sections.

Follow EN 1011-2. Gangsteel optimizes for both.

Applications Comparison

• S275N: Moderate loads, standard bridges, cold moderate.
• S355N: Heavy loads, high-rise, offshore — thinner than S275N.

Why Gangsteel for S275N and S355N?

With ISO-certified quality, Gangsteel supplies both grades tailored to specifications, stocked for immediate export. Visit our en 10025 3 s275n normalized structural steel plate for details.

Summary

S275N and S355N are EN 10025-3 normalized steels with identical -20°C toughness (47 J), but S355N has higher yield (355 MPa vs 275 MPa) and tensile (470–630 MPa vs 370–530 MPa) for heavier loads and thinner designs. S275N is economical for moderate projects; S355N for demanding applications. Both from Gangsteel ensure reliable performance.

FAQ

What is the main difference between S275N and S355N?

S355N has higher minimum yield strength (355 MPa vs 275 MPa for ≤16 mm) and tensile strength (470–630 MPa vs 370–530 MPa), making it stronger for heavier structural demands, while both maintain 47 J impact at -20°C.

Are S275N and S355N equally tough at low temperatures?

Yes, both guarantee 47 J longitudinal (31 J transverse) at -20°C, ensuring comparable resistance to brittle fracture in cold environments like offshore infrastructure.

How do their chemical compositions differ?

S355N allows higher carbon (0.20% vs 0.20%), silicon (0.50% vs 0.40%), manganese (0.90–1.60% vs 0.80–1.60%), and vanadium (0.12% vs 0.05%) for increased strength, with slightly higher CEV (0.43 vs 0.40). Both maintain low P/S for toughness.

When should I use S275N instead of S355N?

Select S275N for cost-sensitive projects with moderate loads, such as standard bridges or light cranes in cold climates, where 275 MPa yield suffices, reducing material costs.

When is S355N preferred over S275N?

Choose S355N for high-strength applications like offshore platforms, heavy bridges, or wind turbine towers, where its 355 MPa yield optimizes structural efficiency and reduces weight.

Are welding requirements different for S275N and S355N?

Both are weldable with low CEV, but S355N's higher CEV (≤0.43) may require 50–100°C preheating for thicknesses >40 mm, compared to S275N (≤0.40). Follow EN 1011-2 for procedures.