SS400 vs S235JR
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.
SS400
Structural & HSLA Steel
SS400 is Japan’s general structural steel under JIS G3101 and one of the most traded structural grades in Asia. The “400” is its minimum tensile class (400–510 MPa); the standard caps only phosphorus and sulfur and leaves carbon and manganese to the mill, so SS400 is bought on mechanical properties, not chemistry.
Standards: DIN 1.0038 (S235JR, near) · AISI A36 (near) · JIS SS400 (JIS G3101) · GB Q235B (near)
S235JR
Structural & HSLA Steel
S235JR is the baseline non-alloy structural steel of EN 10025-2, the default grade for ordinary steel construction across Europe. Its 235 MPa yield class and room-temperature impact guarantee cover the great majority of building and general fabrication work.
Standards: DIN 1.0038 (S235JR) · AISI A36 (near) · JIS SS400 (near) · GB Q235B (near)
Chemical composition compared (%)
| Element | SS400 | S235JR |
|---|---|---|
| P | ≤0.050 | ≤0.035 |
| S | ≤0.050 | ≤0.035 |
| C / Si / Mn | Not specified by JIS G3101 — the grade is defined by its tensile properties, not by chemistry | — |
| C | — | ≤0.17 |
| Mn | — | ≤1.40 |
| Cu | — | ≤0.55 |
Properties compared
| Property | SS400 | S235JR |
|---|---|---|
| Tensile strength | 400–510 MPa | 360–510 MPa |
| Yield strength | ≥245 MPa (≤16 mm) | ≥235 MPa (≤16 mm; falls with thickness) |
| Density | 7.85 g/cm³ | 7.85 g/cm³ |
| Weldability | Excellent in practice (chemistry uncontrolled beyond P/S) | — |
| Impact | — | JR: 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: SS400 · S235JR. Substitution decisions for certified parts stay with the design authority.