What is S355JR?
S355JR is a non-alloy structural steel grade defined in EN 10025-2.
"S" = structural steel
"355" = minimum yield strength of 355 MPa
"JR" = Charpy impact energy of 27 J at 20°C
It is widely used in bridges, building frames, and general engineering structures due to its good weldability, machinability, and toughness at room temperature.
1. Mechanical Properties
| Property | Value / Requirement | Standard / Notes |
|---|---|---|
| Yield Strength (ReH) | ≥ 355 MPa | EN 10025-2 |
| Tensile Strength (Rm) | 470–630 MPa | EN 10025-2 |
| Elongation (A5) | ≥ 20% | Typical for structural steel |
| Impact Energy (Charpy V-notch) | ≥ 27 J at 20°C | "JR" rating |
| Density | 7.85 g/cm³ | Standard steel value |
| Hardness (HB) | ~140–190 HB | Brinell hardness |
2. Chemical Composition (Typical % by weight)
| Element | Max / Typical (%) |
|---|---|
| C | 0.22 |
| Si | ≤ 0.55 |
| Mn | 1.60 |
| P | ≤ 0.035 |
| S | ≤ 0.035 |
| N | ≤ 0.012 |
What is the difference between S355J0 and S355JR?
Difference Between S355J0 and S355JR
| Feature | S355JR | S355J0 |
|---|---|---|
| Yield Strength (ReH) | ≥ 355 MPa | ≥ 355 MPa |
| Tensile Strength (Rm) | 470–630 MPa | 470–630 MPa |
| Impact Energy (Charpy V) | ≥ 27 J at 20°C | ≥ 27 J at 0°C |
| Low-Temperature Use | Suitable for room temperature | Suitable for cooler environments |
| Weldability | Excellent | Excellent |
| Typical Applications | Bridges, buildings, moderate load structures | Bridges, buildings, welded structures in cooler climates |
Key Points
Impact Temperature Rating:
JR: 27 J at 20°C (room temperature)
J0: 27 J at 0°C, offering better low-temperature toughness
Applications:
S355JR: Standard structural steel for general engineering
S355J0: Preferred in cooler climates or slightly lower-temperature environments
Other Properties:
Both grades have the same yield and tensile strength, machinability, and weldability.
What is S355JR equivalent to?
All these equivalents have similar minimum yield strength (~355 MPa) and are structural steels with good weldability and machinability.
Exact chemical composition and impact energy requirements may vary slightly by standard.
S355JR Equivalent Grades
| Country / Standard | Equivalent Grade |
|---|---|
| American (ASTM) | A572 Grade 50 |
| German (DIN) | St 52-3 |
| Italian (UNI) | Fe 510 C |
| Japanese (JIS) | SM490A |
| Chinese (GB) | Q345B |
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.
