A283 Gr.C vs Q235B
These two grades are listed as equivalents of each other: their chemistry windows overlap and they serve the same applications. They are not always identical — check the differences below before substituting, especially in certified designs.
A283 Gr.C
Carbon Steel
ASTM A283 Grade C is a low-to-intermediate tensile carbon steel plate intended for general structural and tank work not requiring code pressure-vessel quality. It is the economy plate grade behind much non-critical US fabrication.
Standards: AISI A283 Gr.C · GB Q235B (near)
Q235B
Structural & HSLA Steel
Q235B is China’s everyday carbon structural steel — the volume grade for domestic construction, plate, sections and welded tube. Grade B adds a room-temperature impact test over the basic A quality, making it the default export offer in this strength class.
Standards: DIN S235JR (near) · AISI A36 (near) · JIS SS400 (near) · GB Q235B (GB/T 700)
Chemical composition compared (%)
| Element | A283 Gr.C | Q235B |
|---|---|---|
| C | ≤0.24 | 0.12–0.20 |
| Si | 0.15–0.40 | ≤0.30 |
| Mn | ≤0.90 | 0.30–0.70 |
| P | ≤0.035 | ≤0.045 |
| S | ≤0.035 | ≤0.045 |
Properties compared
| Property | A283 Gr.C | Q235B |
|---|---|---|
| Yield strength | ≥205 MPa | ≥235 MPa (≤16 mm) |
| Tensile strength | 380–485 MPa | 370–500 MPa |
| Density | 7.85 g/cm³ | 7.85 g/cm³ |
| Impact | — | B grade: 27 J at 20 °C |
Sourcing either grade?
Nasteel stocks both families from Shenzhen with EN 10204 3.1 mill certificates by heat number.
Ask for a quotationSee full data sheets: A283 Gr.C · Q235B. Substitution decisions for certified parts stay with the design authority.