Highest strength TMT grade for specialized heavy infrastructure. Maximum steel savings but lower ductility — use where high strength is the primary requirement.
| Element | Maximum % | Significance |
|---|---|---|
| Carbon (C) | 0.3% | Strength; lower = better weldability |
| Sulphur (S) | 0.04% | Lower = better ductility and toughness |
| Phosphorus (P) | 0.04% | Lower = better cold-bending performance |
| S + P | 0.075% | Combined impurity limit |
| Carbon Equivalent (CE) | 0.42% | Weldability indicator; lower = easier to weld |
| Test | Bar dia ≤ 20mm | Bar dia > 20mm |
|---|---|---|
| Bend test (mandrel dia) | 5d | 6d |
| Rebend test (mandrel dia) | 8d | 10d |
| Diameter (mm) | Area (mm2) | Weight (kg/m) | Weight (kg/12m) |
|---|---|---|---|
| 6 mm | 28.3 | 0.222 | 2.66 |
| 8 mm | 50.3 | 0.395 | 4.74 |
| 10 mm | 78.5 | 0.617 | 7.40 |
| 12 mm | 113.1 | 0.888 | 10.66 |
| 16 mm | 201.1 | 1.578 | 18.94 |
| 20 mm | 314.2 | 2.466 | 29.59 |
| 25 mm | 490.9 | 3.853 | 46.24 |
| 28 mm | 615.8 | 4.834 | 58.01 |
| 32 mm | 804.2 | 6.313 | 75.76 |
| 36 mm | 1017.9 | 7.990 | 95.88 |
| 40 mm | 1256.6 | 9.865 | 118.38 |
Not recommended for primary seismic-resistant members in zones III-V due to lower ductility. Suitable for non-ductile elements and zones I-II.