A36/Q235/S235JR Carbon Steel Coil: Versatile Low-Carbon Structural Steel for Global Construction & Fabrication
A36/Q235/S235JR Carbon Steel Coil Product Overview
The A36/Q235/S235JR carbon steel coil is a general-purpose structural steel with 250 MPa minimum yield strength and 400-550 MPa tensile strength, compliant with ASTM A36, EN 10025-2 S235JR, and GB/T 700 Q235B standards. Combining 0.25-0.29% carbon content and 1.03% manganese, this hot-rolled/cold-rolled steel offers exceptional weldability, formability, and cost efficiency for bridges, buildings, and machinery. With 7.85 g/cm³ density and 200 GPa elastic modulus, it outperforms alternatives like A572 Grade 50 in lightweight structural designs.
Key Technical Specifications
1. Production & Dimensions
- Process:
- Hot-rolled: 2.75–100mm thickness (±1.5% tolerance)
- Cold-rolled: 0.2–3mm thickness (±0.5% tolerance)
- Width: 45–2,200mm (slit-to-width for CNC machining)
- Surface: Mill scale, wire-drawn (Ra 3.2µm), or laminated film (anti-corrosion)
2. Chemical Composition
| Element | A36 (ASTM) | Q235B (GB) | S235JR (EN) | Role |
|---|---|---|---|---|
| Carbon | 0.25–0.29% | 0.12–0.20% | ≤0.17% | Strength |
| Manganese | 1.03% | 0.30–0.65% | 0.40–1.40% | Hardening |
| Phosphorus | ≤0.040% | ≤0.045% | ≤0.030% | Ductility |
| Sulfur | ≤0.050% | ≤0.045% | ≤0.025% | Machinability |
Trace elements: Copper (0.20% min for atmospheric corrosion resistance)
3. Mechanical Properties
| Standard | Yield Strength (MPa) | Tensile Strength (MPa) | Elongation (%) | Impact Energy (J) |
|---|---|---|---|---|
| ASTM A36 | ≥250 | 400–550 | 20 (50mm) | – |
| GB Q235B | ≥235 | 370–500 | 26 (50mm) | 27 @ 20°C |
| EN S235JR | ≥235 | 360–510 | 22 (50mm) | 27 @ -20°C |
Tested per ISO 6892-1 (tensile) & ISO 148-1 (Charpy V-notch)
Performance Advantages
- Weldability & Fabrication:
- Carbon Equivalent (CEV): 0.36 (IIW formula) enables arc/MIG/TIG welding without preheating below 19mm thickness.
- Bend radius: 1.5× thickness (ASTM A370) for CNC press brake forming.
- Corrosion Resistance:
- Atmospheric corrosion rate: 0.075 mm/year (ISO 9223 C2 environment).
- Compatible with epoxy, galvanizing, or powder coating for C5 marine durability.
- Cost Efficiency:
- 20% lower material cost vs. high-strength low-alloy steels (HSLA) like ASTM A572.
- Zero heat treatment required for most structural applications.
Global Equivalents
| ASTM A36 | EN 10025 | GB/T 700 | JIS G3101 | IS 2062 |
|---|---|---|---|---|
| – | S235JR | Q235B | SS400 | E250A |
Applications
| Industry | Use Case | Recommended Thickness |
|---|---|---|
| Construction | Steel framing, I-beams | 6–20mm (hot-rolled) |
| Transport | Truck chassis, trailers | 3–10mm (cold-rolled) |
| Energy | Wind turbine bases | 30–100mm (hot-rolled) |
| Agriculture | Grain silo supports | 2.75–6mm (hot-rolled) |
Sustainability & Compliance
- Recycled Content: 93% (mill-certified)
- RoHS Compliance: Lead <0.01%, Mercury-free
- PED 2014/68/EU: Category I pressure equipment
Packing And Delivery
