China · GB
25
GB/T 699:1999 — Quality carbon structure steels
Chemical composition
| Element | min | max | Similar | Remarks |
|---|---|---|---|---|
| C | 0.22 | 0.29 | ||
| Cr | 0.25 | |||
| Cu | 0.25 | |||
| Mn | 0.5 | 0.8 | ||
| Ni | 0.3 | |||
| P | 0.035 | |||
| S | 0.035 | |||
| Si | 0.17 | 0.37 |
Mechanical properties
| Heat treatment / condition | Yield strength | Tensile strength | Elongation | Reduction of area | Impact energy | Hardness |
|---|---|---|---|---|---|---|
| Semi Finished products, quenched and tempered, d <=, 25 mm | ≥275 | ≥450 | ≥23 | ≥50 | ≥71 KU | HB ≤170 HBS10/3000 |