Materials
Titanium CNC Machining: Cost Drivers and When It Pays Off
Titanium is strong, light and slow to cut. Understand the four cost drivers before you design a part in it.
Key takeaways
- Titanium conducts heat poorly, so the heat stays in the cutter.
- Cutting speeds are roughly one tenth of what aluminium allows.
- Most of the cost is machine time and tool wear, not the material itself.
- Design for fewer setups and shallower pockets to bring the price down.
Why titanium costs so much
Titanium has an unusual mix of properties. It is as strong as some steels at about 45% less weight, and it resists corrosion almost like stainless. Those properties are exactly why it is hard to machine.
It keeps its strength at high temperature. That sounds good until you realise the cutting edge gets hot and stays hot.
The four cost drivers
1. Heat stays at the cutting edge
Titanium conducts heat about 20 times less efficiently than aluminium. Instead of flowing into the chip and the part, heat builds up at the tool tip. Cutters wear fast and need frequent changes.
2. Cutting speed is low
Aluminium might run at 300 m/min. Titanium often runs under 60 m/min, and sometimes under 40. The same toolpath takes many times longer, and machine time is the biggest line on the quote.
3. It work-hardens and galls
Titanium rubs rather than shears if the cutter is dull or the feed is too light. The surface hardens, then the next pass is even harder to cut. Galling welds material to the edge and ruins the finish.
4. Stock removal is slow and careful
Deep pockets mean long toolpaths with light radial cuts. High-pressure coolant helps, but it does not make titanium fast. It only makes it possible.
Grades you will see
| Grade | Name | Strength | Typical use |
|---|---|---|---|
| Grade 2 | Commercially pure | ~345 MPa | Chemical parts, marine, food |
| Grade 5 | Ti-6Al-4V | ~950 MPa | Aerospace, medical, high load |
| Grade 9 | Ti-3Al-2.5V | ~620 MPa | Tubing, bicycle frames |
| Grade 23 | Ti-6Al-4V ELI | ~860 MPa | Implants, cryogenic service |
Grade 5 is the default for structural work. Grade 2 is easier to form and weld, but much weaker.
When titanium pays off
- The part must be light and highly loaded at the same time, such as a drone arm or a robotic link.
- It sees salt water, chlorine or body fluid, where aluminium and steel both struggle.
- The operating temperature is high enough to soften aluminium.
- The part is medical or aerospace and the material is specified by standard.
- A steel part would be too heavy and an aluminium part would be too soft.
When to substitute
- A static bracket at room temperature is usually fine in 6061 or 7075 at a fraction of the cost.
- A wear surface is often better served by 17-4PH stainless or a coated aluminium part.
- A cosmetic housing gains nothing from titanium except a higher price.
- A prototype that will be redesigned next month is rarely worth machining in titanium.
Design choices that cut the price
- Reduce the number of setups. Every re-fixture adds time and risk on titanium.
- Keep pockets shallow and open. Deep narrow pockets are the worst case for tool life.
- Use the largest corner radii the design allows, so a bigger cutter can reach.
- Avoid thin floors. They vibrate, and vibration destroys titanium tools.
- Specify tolerances only where they matter. Tight tolerances on titanium are expensive to inspect and to hold.
- Consider a near-net forging or a printed preform if you are removing more than 70% of the stock.
Common questions
How much more does titanium cost than aluminium?
For the same geometry, expect three to six times the machined price. The gap grows with pocket depth and tolerance.
Can titanium be anodized?
Yes, but the process is different from aluminium anodizing. It is usually done for color marking or wear rather than corrosion protection.
Is titanium hard to tap?
Yes. Threads gall easily. Use forming taps, plenty of lubricant and a slightly larger pilot hole.
The bottom line
Titanium is a performance material, not a default. If the load case or the environment demands it, design for fewer setups and shallower cuts so you pay for the metal rather than for the clock.