S355 steel is the reference material for demanding industrial projects. Offering a mechanical resistance significantly higher than S235 and S255 grades, it allows for the design of lighter and more robust structures. This technical datasheet details its properties and applications to support you in your engineering choices.
S355 steel is a non-alloy structural steel with a high yield strength. Governed by the European standard EN 10025-2, it is preferred when load constraints are high or when the total weight of the structure must be optimized.
Its nomenclature indicates its superior mechanical performance.
| Symbol | Meaning | Explanation |
|---|---|---|
| S | Structural | Steel intended for construction applications. |
| 355 | Yield Strength | Guarantees a minimum yield strength of 355 MPa (N/mm²). |
| J2 / K2 | Impact Strength | Unlike the standard JR, S355 is often ordered in J2 (27 J at -20°C) or K2 (40 J at -20°C) quality for cold environments or dynamic loads. |
S355 offers a major performance leap (+50% yield strength compared to S235).
S355 is indispensable where structural safety and lightness are critical.
| Advantages | Points of Vigilance |
|---|---|
| High Performance: High load capacity for complex structures. | Springback: More significant during bending and requires machine expertise. |
| Weight Optimization: Reduced steel consumption and transportation costs. | Protection: Requires painting or galvanizing (Magnelis® recommended for outdoor use). |
| Reliability: Excellent impact resistance, especially in J2/K2 quality. | Price: Higher cost per kilo, offset by material savings. |
S355 steel is the “muscle” of the industry. With a yield strength 50% higher than S235, it is indispensable for lifting equipment, transportation chassis, and critical infrastructure.
ArcelorMittal (Amstrong® range), SSAB, Dillinger.
| EN Standard (Europe) | ASTM Standard (USA) | Old DIN Standard (DE) | JIS Standard (JP) |
|---|---|---|---|
| S235JR | A36 | St 37-2 | SS400 |
| S255JR | A570 Gr. 40 | St 42 | - |
| S355J2 | A572 Gr. 50 | St 52-3 | SM490 |
For S355, we often recommend J2 quality (impact resistance at -20°C) for outdoor structures or components subject to heavy vibrations.
| Feature | S235 Steel | S255 Steel | S355 Steel |
|---|---|---|---|
| Yield Strength (Re) | 235 MPa | 255 MPa | 355 MPa |
| Structural Performance | Standard / Moderate | Intermediate | High Performance |
| Structural Weight | Heavier (wider sections) | Optimized Balance | Maximum Weight Saving |
| Weldability | Excellent (very easy) | Excellent | Very Good |
| Bending Suitability | Maximum | Very Good | Good (watch springback) |
| Material Cost | Economic (€) | Moderate (€+) | Higher (€€) |
| Stock Availability | Universal | Upon Request / Projects | Very Common |
At Baguet Métal, we process S355 steel with the precision required by your drawings. Thanks to our CNC cutting and bending centers, we guarantee strict compliance with geometric tolerances.
Unsure whether to choose S235, S255 or S355?
Our experts analyze your load constraints and recommend the most cost-effective grade for your application.
