M4 vs M2
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.
M4
Tool Steel
M4 raises carbon and vanadium to about 4% each over the M2 base, giving outstanding abrasive wear resistance among conventional (non-PM) high-speed steels. It is a premium choice for punches and heavy-duty cutters.
Standards: DIN — (HS6-5-4 family) · AISI M4 · JIS SKH57 (near) · GB W6Mo5Cr4V3
M2
Tool Steel
M2 is the most widely used high-speed steel in the world, balancing red hardness, toughness and cost for cutting tools of every kind.
Standards: DIN 1.3343 · AISI M2 · JIS SKH51 · GB W6Mo5Cr4V2
Chemical composition compared (%)
| Element | M4 | M2 |
|---|---|---|
| C | 1.25–1.40 | 0.78–0.88 |
| Si | ≤0.45 | ≤0.45 |
| Mn | ≤0.40 | ≤0.40 |
| Cr | 3.75–4.75 | 3.80–4.50 |
| Mo | 4.00–5.50 | 4.70–5.20 |
| W | 5.25–6.75 | 5.90–6.70 |
| V | 3.75–4.75 | 1.70–2.10 |
Properties compared
| Property | M4 | M2 |
|---|---|---|
| Delivery condition | Annealed | Annealed |
| Hardness (hardened) | 63–66 HRC | 63–66 HRC |
| Density | 7.95 g/cm³ | 8.10 g/cm³ |
| Wear resistance | Very high (4% vanadium) | — |
| Red hardness | — | To ~600 °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: M4 · M2. Substitution decisions for certified parts stay with the design authority.