Comparison of A36, SS400, and Q235 H-Beams
A36 H-beam is similar to Q235B H-beam. Another equivalent standard is SS400. The differences between these H-beams are as follows:
Mechanical Properties
| Steel Grade | Yield Strength (MPa) | Tensile Strength (MPa) |
|---|---|---|
| ASTM A36 | 250 | 400–550 |
| GB Q235B | 235 | 375–500 |
| JIS SS400 | 245 | 400–510 |
Chemical Composition
| Steel Grade | C | Mn | Si | S | P | Cu |
|---|---|---|---|---|---|---|
| ASTM A36 | ≤0.26 | – | ≤0.40 | ≤0.05 | ≤0.04 | ≥0.2 |
| GB Q235A | 0.14–0.22 | 0.30–0.65 | ≤0.30 | ≤0.05 | ≤0.045 | – |
| GB Q235B | 0.12–0.20 | 0.30–0.70 | ≤0.30 | ≤0.045 | ≤0.045 | – |
| JIS SS400 | – | – | – | ≤0.05 | ≤0.05 | – |
Analysis
Mechanical equivalence: From a mechanical perspective, A36 and SS400 H-beams are more closely equivalent. Q235B H-beams have slightly lower mechanical properties but can often be substituted in general construction projects.
Substitution: For most engineering applications, as long as there are no strict mechanical requirements, A36, SS400, and Q235B H-beams can be interchanged.
Standard designation:
A36: ASTM/ASME (USA)
SS400: JIS G3101 (Japan)
Q235: GB700 (China)
Element requirements: Q235B specifies C, Si, Mn, S, and P contents. A36 only limits C, Si, S, and P, with Mn content optional depending on thickness. SS400 only limits S and P, other elements are not strictly defined.
Key Comparison for H-Beams
| Feature | ASTM A36 | GB Q235B | JIS SS400 |
|---|---|---|---|
| Yield Strength | 250 MPa | 235 MPa | 245 MPa |
| Tensile Strength | 400–550 MPa | 375–500 MPa | 400–510 MPa |
| Carbon Content | ≤0.26% | 0.12–0.20% | – |
| Manganese Content | – | 0.30–0.70% | – |
| Silicon Content | ≤0.40% | ≤0.30% | – |
| Sulfur Content | ≤0.05% | ≤0.045% | ≤0.05% |
| Phosphorus Content | ≤0.04% | ≤0.045% | ≤0.05% |
| Copper Content | ≥0.2% | – | – |
| Typical Applications | Structural columns, beams, bridges, platforms | Same as A36 | Same as A36 |
