D2 is a high-carbon, high-chromium cold-work tool steel with excellent wear resistance. The chromium carbides that give it that wear resistance also make it abrasive and tough to machine, so run slow with hard coatings.
Key properties
| Property | Typical value |
|---|---|
| Density | 0.278 lb/in³ (7.70 g/cm³) |
| Hardness (annealed) | ~217 HB |
| Hardness (hardened) | 58–62 HRC |
| Machinability (annealed) | Poor (abrasive) |
| Composition | Fe with ~12% Cr, C, Mo, V |
Cutting speeds
| Operation | HSS (SFM) | Carbide (SFM) |
|---|---|---|
| Milling | 40 – 60 | 150 – 300 |
| Turning | 50 – 70 | 200 – 350 |
| Drilling | 30 – 50 | 120 – 220 |
Convert to RPM: RPM = (SFM × 3.82) / cutter diameter. Use the Feeds & Speeds calculators.
Tooling and tips
- Expect abrasive wear from the chromium carbides — AlTiN carbide holds up best.
- Machine annealed; hardened D2 needs grinding or EDM.
- Rigid setup, flood coolant, and patience — do not rush the speeds.
See Cutting Speeds for Steel and the full Feeds and Speeds Chart.