What is S420NL?
S420NL is a normalized/normalized-rolled, fine-grain structural steel defined in EN 10025-3.
The "S" stands for structural steel, 420 is the minimum yield strength (MPa) for thin sections, and NL indicates good low-temperature toughness (Charpy impact tested at –50°C).
It is widely used for bridges, offshore structures, cranes, wind towers, heavy machinery, and low-temperature engineering applications.
1. Chemical Composition (Typical Values, %)
| Element | C (max) | Si | Mn | P (max) | S (max) | Nb | V | Ti |
|---|---|---|---|---|---|---|---|---|
| S420NL | 0.20 | ≤ 0.60 | 1.00–1.70 | 0.025 | 0.020 | ≤ 0.06 | ≤ 0.14 | ≤ 0.05 |
2. Mechanical Properties
| Property | Value |
|---|---|
| Yield Strength (≤ 16 mm) | 420 MPa |
| Yield Strength (40–100 mm) | 380–400 MPa |
| Tensile Strength | 520–680 MPa |
| Elongation (A5) | ≥ 19% |
| Impact Toughness | ≥ 27 J at –50°C |
| Density | 7.85 g/cm³ |
What is S460NL?
S460NL is a normalized/normalized-rolled fine-grain structural steel specified in EN 10025-3.
The designation means:
S = Structural steel
460 = Minimum yield strength of 460 MPa (for thickness ≤ 16 mm)
N = Normalized or normalized-rolled
L = Guaranteed low-temperature toughness (Charpy impact at –50°C)
It is used in high-strength load-bearing structures, such as bridges, offshore platforms, cranes, wind towers, and heavy industrial equipment.
1. Chemical Composition (Typical Values, %)
| Element | C (max) | Si | Mn | P (max) | S (max) | Nb | V | Ti |
|---|---|---|---|---|---|---|---|---|
| S460NL | 0.20 | ≤ 0.60 | 1.00–1.80 | 0.025 | 0.020 | ≤ 0.06 | ≤ 0.14 | ≤ 0.05 |
2. Mechanical Properties
| Property | Value |
|---|---|
| Yield Strength (≤ 16 mm) | 460 MPa |
| Yield Strength (40–100 mm) | 420–440 MPa |
| Tensile Strength | 540–720 MPa |
| Elongation (A5) | ≥ 17–19% |
| Impact Toughness | ≥ 27 J at –50°C |
| Density | 7.85 g/cm³ |
Which one should I choose?
| Requirement | Choose S420NL | Choose S460NL |
|---|---|---|
| Strength level | Adequate for general heavy structures | Needed for higher load-bearing capacity |
| Weight reduction | Not optimal | Better (higher strength = thinner plates possible) |
| Budget sensitivity | More economical | Higher cost per ton |
| Welding complexity | Slightly easier | Requires more control but still weldable |
| Low-temperature performance | Excellent | Excellent (similar impact toughness) |
| Typical use | Standard construction, machinery, moderate loads | Bridges, offshore, cranes, wind towers, high-stress structures |
Simple recommendation
Choose S420NL if your structure does not require very high strength, and you want lower cost, easier welding, and reliable toughness.
Choose S460NL if you need higher structural performance, weight reduction, or are working on high-stress or safety-critical projects.
GNEE Steel also supplies a variety of high-strength steel plates, such as A514 Grade F, A572 Grade 50, A588 Grade A, S355JR, S690Q, SS400, S690QL, Q345B, Q345E, etc. If you want to know more about other types of steel plates, you can call the consultation hotline at +8615824687445 or send an email to info@gneesteels.com. You are welcome to consult us, and we are very willing to answer your questions.
