S1 vs 1.2550
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.
S1
Tool Steel
S1 is the original tungsten shock-resisting tool steel, built for tools that take repeated hammer blows. Its Cr-W chemistry gives safe hardening with outstanding toughness at working hardness.
Standards: DIN 1.2550 (close) · AISI S1 · GB 5CrW2Si (near)
1.2550
Tool Steel
1.2550 (60WCrV7) is the European tungsten shock-resisting tool steel, the close counterpart of AISI S1. It is a staple for chisels, punches and shear blades across European shops.
Standards: DIN 1.2550 · AISI S1 (close) · GB 6CrW2Si (near)
Chemical composition compared (%)
| Element | S1 | 1.2550 |
|---|---|---|
| C | 0.40–0.55 | 0.55–0.65 |
| Si | 0.15–1.20 | 0.50–0.80 |
| Mn | 0.10–0.40 | 0.15–0.45 |
| Cr | 1.00–1.80 | 0.90–1.20 |
| W | 1.50–3.00 | 1.80–2.10 |
| V | 0.15–0.30 | 0.10–0.20 |
Properties compared
| Property | S1 | 1.2550 |
|---|---|---|
| Delivery condition | Annealed | Annealed |
| Hardness (hardened) | 50–58 HRC | 50–58 HRC |
| Density | 7.85 g/cm³ | 7.85 g/cm³ |
| Toughness | Excellent (shock-resisting) | High (shock-resisting class) |
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: S1 · 1.2550. Substitution decisions for certified parts stay with the design authority.