S355NL and S355J0 are both European standard (EN 10025) high-strength structural steels with a minimum yield strength of 355 MPa, but they differ in delivery condition and toughness, making S355NL superior for cold climates: S355NL is fine-grain, normalized, and tested to -50°C impact (≥27 J), ideal for arctic/offshore use, while S355J0 is typically hot-rolled (or normalized if specified as +N) with less stringent -20°C toughness, suitable for general construction in milder environments.
Mechnical property for S355J0 steel plate:
| Thickness (mm) | |||||||||
| S355J0 | ≤ 16 | > 16 ≤ 40 | > 40 ≤ 63 | > 63 ≤ 80 | > 80 ≤ 100 | > 100 ≤ 150 | > 150 ≤ 200 | > 200 ≤ 250 | > 250 |
| Yield strength (≥Mpa) | 355 | 345 | 335 | 325 | 315 | 295 | 285 | 275 | 275 |
| < 3 | ≥ 3 ≤ 100 | > 100 ≤ 150 | > 150 ≤ 250 | > 250 | |||||
| Tensile strength (Mpa) | 510-680 | 470-630 | 450-600 | 450-600 | 450-600 | ||||
Mechnical property for S355NL steel plate:
| Grade | Thickness(mm) | Min Yield (Mpa) | Tensile(MPa) | Elongation(%) | Min Impact Energy | |
| S355NL | 8mm-100mm | 235Map-275Mpa | 470-630Mpa | 22% | -50 | 27J |
| 101mm-200mm | 285Mpa-315Mpa | 450-600Mpa | 21% | -50 | 27J | |
| 201mm-250mm | 275Mpa-285Mpa | 450-600Mpa | 21% | -50 | 27J | |
| The min impact energy is longitudinal energy | ||||||
Chemical composition for S355J0 steel plate
| Main chemical elements composition of S355J0 steel plate | |||||||
| Thickness(mm) | C | Si | Mn | P | S | N | Cu |
| T≤16 | 0.20 | 0.55 | 1.60 | 0.030 | 0.030 | 0.012 | 0.55 |
| 16<T≤40 | 0.20 | ||||||
| 40<T | 0.22 | ||||||
Chemical composition for S355NL steel plate
| Grade | C % | Si % | Mn % | P % | S % | V % | AL % | Cr % |
| S355NL | 0.180 | 0.500 | 0.9-1.65 | 0.025 | 0.020 | 0.120 | 0.020 | 0.300 |
| Cu % | Mo % | Nb % | Ni % | Ti % | N % | |||
| 0.550 | 0.100 | 0.050 | 0.300 | 0.050 | 0.015 |
S355NL (Normalized)
Condition: Fine-grain, supplied normalized (or normalized rolled) for better toughness.
Toughness: High, guaranteed ≥27 Joules at -50°C, excellent for very cold conditions.
Weldability: Better due to lower Carbon Equivalent (CEV), requiring less preheat.
Applications: Offshore platforms, wind towers, cold-climate bridges, heavy-duty welded structures.
S355J0 (Hot-Rolled/Normalized)
Condition: Hot-rolled (if just J0) or normalized (if J0+N).
Toughness: Good, but typically guaranteed ≥27 Joules at 0°C (if J0) or -20°C (if J0+N), suitable for temperate zones.
Weldability: Good, but slightly higher CEV than NL.
Applications: General structural frameworks, bridges, machinery in moderate climates.
