55Cr3 vs 5150
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.
55Cr3
Alloy & Engineering Steel
55Cr3 is the EN chromium spring steel (1.7176) for hot-rolled spring bar and flat products. It occupies the same niche as SAE 5155/5160 in European spring making, with tighter phosphorus and sulfur limits.
Standards: DIN 1.7176 (55Cr3) · AISI 5155 (near) · JIS SUP9 family (near) · GB 55CrMnA (near)
5150
Alloy & Engineering Steel
5150 is a medium-high carbon chromium steel used for stronger springs, axles and gears. It is the chromium-step between plain 1050 and the full spring grade 5160.
Standards: DIN 50Cr4 type (near) · AISI 5150 · JIS SCr445 (near) · GB 50Cr
Chemical composition compared (%)
| Element | 55Cr3 | 5150 |
|---|---|---|
| C | 0.52–0.59 | 0.48–0.53 |
| Si | ≤0.40 | 0.15–0.35 |
| Mn | 0.70–1.00 | 0.70–0.90 |
| P | ≤0.025 | ≤0.035 |
| S | ≤0.025 | ≤0.040 |
| Cr | 0.70–1.00 | 0.70–0.90 |
Properties compared
| Property | 55Cr3 | 5150 |
|---|---|---|
| Hardness (spring temper) | 40–48 HRC typical | — |
| Tensile strength | 1200–1500 MPa (Q&T spring temper, typ.) | 900–1150 MPa (Q&T, typ.) |
| Density | 7.85 g/cm³ | 7.85 g/cm³ |
| Hardness (Q&T) | — | 30–42 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: 55Cr3 · 5150. Substitution decisions for certified parts stay with the design authority.