15F
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 15F →15F · 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, row 3, Table 2 and Clause 6.1.1
- PDF page references
- 5、6
- Unit
- Mass fraction (%)
- Analysis type
- Ladle analysis
Carbon-equivalent reference
Composition
| Element | Composition requirement |
|---|---|
| C | 0.12 ～ 0.18 |
| Si | ≤ 0.07 (lower limit not stated) |
| Mn | 0.25 ～ 0.5 |
| 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
Edition 1999, main-text Table 1, row 3, unified numerical designation U20150. This record uses the default quality-steel class; heat analysis, mass fraction %. Table 2: for quality steel, P and S are each ≤0.035%; for higher-quality class A, each is ≤0.030%; for special-quality class E, the requirements are P≤0.025% and S≤0.020%. Do not apply A/E limits to the default class. 6.1.1.2—3: scrap-based steelmaking may permit Cu≤0.30%; steel for hot pressure working requires Cu≤0.20%. This record retains the default Cu≤0.25% in Table 1; specific conditions require separate confirmation. 6.1.1.4: Mn/Cr/Ni/Cu for lead-patented steel wire 35—85 has a separate restriction and does not apply to this default structural-steel record. Mechanical properties in Table 3 and 6.4 depend on specimens, dimensions, heat treatment and order requirements. Existing reference properties are not upgraded to universal guarantees by this composition review.