25B
1 source records. Standards, editions and conditions are presented separately; matching grade names do not establish interchangeability.
Refer to each source for mass fractions and analysis type. Missing values are not treated as 0. Manufacturer typical values, standard guarantees and measured heat results must remain separate. Use the material selector for calculations and condition selection.
Open condition selection, comparison and carbon-equivalent tools for 25B →25b · GB/T 699-1999
Chemical composition source verified; this does not verify every standard clause, actual supply or measured heat results
- Material category
- Carbon steel
- Material form
- Quality carbon structural steel (source classification)
- Original record status
- Original standard verified
- Standard edition
- GB/T 699-1999
- Table / clause
- Main text: Table 1 / Table 2 / 6.1.1.8
- PDF page references
- 5、6
- Unit
- Mass fraction (%)
- Analysis type
- Ladle analysis
Carbon-equivalent reference
Composition
| Element | Composition requirement |
|---|---|
| C | 0.22 ～ 0.29 |
| Si | ≤ 0.17 (lower limit not stated) |
| Mn | 0.5 ～ 0.8 |
| Cr | ≤ 0.25 (lower limit not stated) |
| Ni | ≤ 0.3 (lower limit not stated) |
| Cu | ≤ 0.25 (lower limit not stated) |
| P | ≤ 0.035 (lower limit not stated) |
| S | ≤ 0.035 (lower limit not stated) |
Applicability and limitations
6.1.1.8: 25b and Si≤0.17% apply only when supply of 08—25 semi-killed steel is agreed between purchaser and supplier; this is not a default grade in Table 1. The original Table 2 gives default quality-steel limits P and S≤0.035%; higher or special quality must be selected separately.