S235JR (and S235J0) is a non-alloy structural steel grade specified under EN 10025-2, widely used for structural components requiring good strength, weldability, and toughness at room temperature or low temperature.
The steel is supplied mainly in the hot-rolled, controlled rolled, or normalized condition, depending on customer requirements.
The grade name S235 indicates a minimum yield strength of 235 MPa for thicknesses up to 16 mm, while the suffix JR / J0 refers to the required impact energy performance.
Mechanical Properties of S235JR at Room Temperature
The mechanical properties of S235JR steel vary with plate or section thickness. The table below summarizes the minimum yield strength and tensile strength according to EN 10025-2.
Mechanical Properties – S235JR
| Thickness (mm) | Minimum Yield Strength (MPa) | Tensile Strength (MPa) |
|---|---|---|
| ≤ 16 | 235 | 360 – 510 |
| >16 ≤ 40 | 225 | 360 – 510 |
| >40 ≤ 100 | 215 | 360 – 510 |
| >100 ≤ 150 | 195 | 350 – 500 |
| >150 ≤ 200 | 185 | 340 – 490 |
| >200 ≤ 250 | 175 | 340 – 490 |
| >250 ≤ 400 | 165 | 330 – 480 |
Explanation:
As thickness increases, yield strength decreases slightly due to rolling and cooling effects. However, S235JR still maintains stable tensile strength and good structural reliability across all thickness ranges.
Mechanical Properties of S235J0
S235J0 is a variant of S235 steel with guaranteed impact toughness at 0°C, making it suitable for structures exposed to moderate cold environments.
Minimum Yield Strength – S235J0
| Thickness (mm) | Yield Strength ≥ (MPa) |
|---|---|
| ≤ 16 | 235 |
| >16 ≤ 40 | 225 |
| >40 ≤ 63 | 215 |
| >63 ≤ 80 | 195 |
| >80 ≤ 100 | 195 |
| >100 ≤ 125 | 195 |
Tensile Strength – S235J0
| Thickness (mm) | Tensile Strength (MPa) |
|---|---|
| ≤ 100 | 360 – 510 |
| >100 ≤ 150 | 350 – 500 |
| >150 ≤ 250 | 340 – 490 |
Minimum Elongation of S235J0
The elongation values of S235J0 are measured using the formula Lo = 5.65 × √So, ensuring sufficient ductility for forming and fabrication.
Minimum Elongation (A)
| Thickness (mm) | Minimum Elongation (%) |
|---|---|
| ≤ 16 | 26 |
| >16 ≤ 40 | 25 |
| >40 ≤ 63 | 24 |
| >63 ≤ 100 | 22 |
Explanation:
Higher elongation values indicate better plastic deformation ability, making S235J0 ideal for bending, forming, and welding applications.
Impact Test Requirement
S235JR: Impact test at +20°C, minimum 27 J
S235J0: Impact test at 0°C, minimum 27 J
This ensures resistance to brittle fracture and improves safety in structural applications.
Meaning of S235J0 Steel Grade
"235": Minimum yield strength of 235 MPa for thickness ≤ 16 mm
"J0": Minimum impact energy of 27 Joules at 0°C
This designation confirms that S235J0 steel is suitable for structures requiring both strength and low-temperature toughness.
1. What is S275JR steel?
S275JR is a non-alloy structural steel grade under EN 10025-2. The "S" stands for structural steel, "275" refers to the minimum yield strength of 275 MPa, and "JR" indicates an impact energy of 27 Joules at +20°C.
2. What is the minimum yield strength of S275JR?
The minimum yield strength of S275JR is 275 MPa for thicknesses up to 16 mm. For thicker sections, the yield strength may slightly decrease according to EN 10025-2 standards.
3. What is the tensile strength of S275JR?
The typical tensile strength ranges from 410 to 560 MPa, providing a good balance between strength and ductility for structural applications.
4. What impact test is required for S275JR?
S275JR must pass a Charpy V-notch impact test with a minimum energy of 27 Joules at +20°C. It is not intended for low-temperature service.
5. What is the chemical composition of S275JR?
S275JR has low carbon content and includes manganese, silicon, phosphorus, sulfur, and copper in controlled amounts. This ensures good weldability and formability.
6. Is S275JR weldable?
Yes, S275JR offers excellent weldability with conventional welding methods such as MIG, MAG, TIG, and SMAW. Preheating is generally not required for thin and medium thickness plates.
7. Can S275JR be formed?
S275JR can be both cold-formed and hot-formed. Its low carbon equivalent makes it suitable for bending, rolling, and shaping operations.
8. What product forms are available for S275JR?
S275JR is commonly supplied in plates, sheets, beams, channels, angles, and flat bars for structural applications.
9. What are the typical applications of S275JR?
S275JR is widely used in building and bridge construction, steel frames, machinery supports, fabricated steel components, and general engineering structures.
10. How does S275JR compare with S235JR?
Compared to S235JR, S275JR has higher yield strength, better load-bearing capacity, and improved structural performance, while maintaining similar weldability and processing characteristics.
11. Is S275JR suitable for outdoor use?
S275JR does not have inherent corrosion resistance. Surface treatments such as painting, galvanizing, or coating are recommended for outdoor applications. For environments requiring weathering steel, other grades like S355J2W are more suitable.
12. What standards and equivalents relate to S275JR?
Common equivalents include ASTM A36, DIN St44, and BS 40B. Exact equivalency should be verified according to project requirements.