Ti-6Al-4V Milling — Recommended Cutting Parameters
Recommended cutting speeds, feeds, and depths of cut for milling Ti-6Al-4V (Grade 5) titanium. Data sourced from machining handbooks and validated production experience.
| Property | Value | Unit | Notes |
|---|---|---|---|
| Rough Milling Speed | 40-60 | m/min (130-200 SFM) | Use lower end for heavier DOC |
| Finish Milling Speed | 60-90 | m/min (200-300 SFM) | Higher speeds for lighter cuts |
| Feed per Tooth (Rough) | 0.10-0.20 | mm/tooth | Depends on insert geometry |
| Feed per Tooth (Finish) | 0.05-0.12 | mm/tooth | Lower for better surface finish |
| Depth of Cut (Radial) | 0.5-2.0 | mm | 30-50% of cutter diameter for roughing |
| Depth of Cut (Axial) | 0.5-5.0 | mm | Full depth for slotting |
| Coolant Pressure | 70-100 | bar | High-pressure through-spindle coolant recommended |
Quick Answer
For milling Ti-6Al-4V, use cutting speeds of 40-90 m/min, feed rates of 0.05-0.20 mm/tooth, and high-pressure coolant (70-100 bar). Rough at lower speeds with heavier DOC; finish at higher speeds with lighter cuts.
Recommended Cutting Parameters
| Operation | Speed (m/min) | Speed (SFM) | Feed per Tooth (mm) | Radial DOC (mm) | Axial DOC (mm) |
|---|---|---|---|---|---|
| Rough Milling | 40-60 | 130-200 | 0.10-0.20 | 0.5-2.0 | 2.0-5.0 |
| Finish Milling | 60-90 | 200-300 | 0.05-0.12 | 0.3-1.0 | 0.5-2.0 |
| Slotting | 30-50 | 100-165 | 0.08-0.15 | Full width | 0.5-1.5 |
Comparison with Other Materials
| Parameter | Ti-6Al-4V | Al 6061 | Steel 4140 |
|---|---|---|---|
| Cutting Speed (m/min) | 40-90 | 300-800 | 120-250 |
| Feed per Tooth (mm) | 0.05-0.20 | 0.10-0.30 | 0.08-0.25 |
| Coolant Pressure | 70-100 bar | Optional | 10-30 bar |
| Tool Life (relative) | 1x | 10-20x | 3-5x |
Engineering Notes
- Climb Milling Preferred: Reduces work hardening and extends tool life
- Tool Engagement: Keep radial engagement at 30-50% of cutter diameter
- Chip Thinning: Adjust feed rates for small radial engagements
- Tool Path: Use trochoidal milling for deep slots to manage heat
- Coolant: Through-spindle coolant at 70+ bar is strongly recommended
Sources
- Sandvik Coromant Titanium Machining Guide
- Machining Data Handbook, 3rd Edition, Metcut Research Associates
- Seco Tools Titanium Machining Recommendations
Engineering Interpretation
The cutting data are from the Machining Data Handbook (Metcut Research Associates) and the Sandvik Coromant titanium machining guidance. Engineering interpretation (titanium.blog): titanium cutting speeds sit far below steel because low thermal conductivity traps heat at the tool edge; the practical levers for tool life are climb milling, holding radial engagement at 30-50% of cutter diameter, and high-pressure through-spindle coolant (70+ bar). These are recommendations to validate per-machine, not absolutes.
Evidence Basis
Based on published cutting data from the Machining Data Handbook (Metcut Research Associates) and Sandvik Coromant titanium machining guidance.