1040 vs 5140
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.
1040
Carbon Steel
1040 is a medium carbon steel for moderately stressed shafts, bolts and gears. It is the plain-carbon predecessor of 5140/40Cr in many cost-sensitive designs, with similar carbon but no chromium hardenability boost.
Standards: DIN 1.0511 (C40) · AISI 1040 · JIS S40C · GB 40
5140
Alloy & Engineering Steel
5140 is a medium-carbon chromium steel for moderately loaded shafts, gears and bolts — the chromium-only (no molybdenum) economy alternative to 4140.
Standards: DIN 1.7035 (41Cr4) · AISI 5140 · JIS SCr440 · GB 40Cr
Chemical composition compared (%)
| Element | 1040 | 5140 |
|---|---|---|
| C | 0.37–0.44 | 0.38–0.43 |
| Mn | 0.60–0.90 | 0.70–0.90 |
| P | ≤0.040 | — |
| S | ≤0.050 | — |
| Si | — | 0.15–0.35 |
| Cr | — | 0.70–0.90 |
Properties compared
| Property | 1040 | 5140 |
|---|---|---|
| Tensile strength | 570–660 MPa (normalized, typ.) | 850–1050 MPa (Q&T) |
| Density | 7.85 g/cm³ | 7.85 g/cm³ |
| Hardness (Q&T) | — | 28–38 HRC typical |
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: 1040 · 5140. Substitution decisions for certified parts stay with the design authority.