What is titanium CNC machining?
Titanium CNC machining is the production of precision parts from titanium and titanium alloys by milling, turning and 5-axis machining. Titanium offers strength close to steel at about half the weight, outstanding corrosion resistance and biocompatibility.
These properties make it essential for aerospace structures, medical implants, defence components and high-performance motorsport parts. The same properties also make it hard to machine, so choosing a manufacturer experienced with titanium is decisive for quality and cost.
Why is titanium hard to machine?
| Property | Effect | What the manufacturer does |
|---|---|---|
| Low thermal conductivity | Heat builds up in the cutting zone and tool | Low cutting speeds, high-pressure coolant |
| Low elastic modulus | The part flexes and chatters during cutting | Rigid fixturing, short tools, suitable fixtures |
| Chemical reactivity | Chips weld to the tool, causing rapid wear | Coated carbide tools, sharp cutting edges |
| High strength | Cutting forces are high | Powerful, rigid machines |
For these reasons titanium takes several times longer to machine than aluminum and noticeably longer than steel.
Titanium grades
| Grade | Type | Key property | Typical use |
|---|---|---|---|
| Grade 2 | Commercially pure titanium | Best corrosion resistance, good formability | Chemical, marine, heat exchangers |
| Grade 5 (Ti-6Al-4V) | Alpha-beta alloy | High strength (tensile around 900 MPa and above) | Aerospace, defence, motorsport |
| Grade 23 (Ti-6Al-4V ELI) | High-purity Grade 5 | Higher toughness, biocompatibility | Medical implants, surgical instruments |
| Grade 9 (Ti-3Al-2.5V) | Alpha-beta alloy | Balance between Grade 2 and Grade 5 | Tubing and hydraulic lines, bicycle frames |
Density is about 4.4–4.5 g/cm³ depending on grade (about 57% of steel). Mechanical values are typical references; exact values come from the material certificate.
Applications
| Industry | Typical parts |
|---|---|
| Aerospace | Brackets, fasteners, structural parts, engine components |
| Medical | Implants, bone screws, surgical instrument parts |
| Defence | Lightweight structural components, housings and fittings |
| Motorsport | Fasteners, suspension and exhaust parts |
| Chemical and marine | Corrosion-resistant fittings, pump and valve components |
Tolerances and surface finish
| Feature | Standard | On request |
|---|---|---|
| General tolerance | ISO 2768-m | ISO 2768-f |
| Critical dimensions | ±0.05 mm | ±0.01–0.02 mm |
| Surface roughness | Ra 1.6–3.2 µm | Ra 0.8 µm and below, polishing |
| Inspection | Standard measurement | CMM report, first article inspection (FAI) |
Because titanium flexes, holding tight tolerances on thin-walled parts is harder. Mark critical dimensions and datums clearly on the drawing.
Design guidelines
- Avoid thin walls; titanium chatters during machining. Where possible, stay above 1.5–2 mm.
- Use internal corner radii as large as possible; small tools wear quickly in titanium.
- Avoid deep, narrow pockets; prefer geometries that can be cut with short, rigid tools.
- Keep thread depth only as deep as the function requires.
- As the material is expensive, near-net-shape designs that reduce material removal lower cost.
Surface finishes
| Finish | What it provides |
|---|---|
| Titanium anodizing | Colouring and identification through the oxide layer (colour coding in medical) |
| Passivation | Improved corrosion resistance |
| Bead blasting | Uniform matte surface |
| Electropolishing | Smooth, easy-to-clean surface (medical) |
| PVD coating | Wear resistance and decorative finish |
Titanium anodizing differs from aluminum anodizing: the colour comes from the thickness of the oxide layer, not from dye.
Material certificates and traceability
| Document / standard | Description |
|---|---|
| EN 10204 3.1 | Material certificate validated by the mill’s independent inspection |
| ASTM B348 | Standard for titanium bars and billets |
| ASTM F136 | Ti-6Al-4V ELI for surgical implants |
| AMS 4928 | Ti-6Al-4V bars and forgings for aerospace |
Material certificates and traceability are usually mandatory for aerospace, medical and defence parts. State the required standard in your request; manufacturers include it in the price.
What drives titanium machining cost
- Material price: titanium costs many times more than aluminum and steel.
- Machining time: low cutting speeds and long cycle times.
- Tooling cost: tool wear is high.
- Tolerance, finish and inspection requirements.
- Certification and documentation.
To reduce cost: avoid tight tolerances that are not functionally required, simplify the design and assess whether you really need titanium’s properties; in some applications aluminum 7075 or stainless steel can be far more economical.
What we need for a quote
- 3D model in STEP format
- PDF drawing showing tolerances, threads and surface roughness
- Titanium grade (Grade 2, Grade 5, Grade 23, etc.)
- Quantity and surface finish
- Material certificate, inspection report or first article inspection requirements
- Any industry standard to comply with (aerospace, medical)
Frequently asked questions
Should I choose titanium or aluminum?
Titanium is chosen where low weight and high strength are needed together, or where resistance to aggressive environments or biocompatibility is required. Without these requirements, aluminum is far more economical and faster to machine.
Why is titanium CNC machining expensive?
The material itself is expensive and, because of its low thermal conductivity, it is machined at low cutting speeds. Tool wear is also high; together these factors increase cost.
What is the difference between Grade 5 and Grade 23?
Grade 23 is the high-purity version of Grade 5 (Ti-6Al-4V) with lower oxygen and iron content. It offers higher toughness and is preferred for medical implants.
Can I get material certificates for titanium parts?
Yes. You can request an EN 10204 3.1 material certificate and, if needed, an inspection report. State your requirements in the quote request.
Can titanium parts be coloured?
Yes. Titanium anodizing produces colours such as gold, blue and purple depending on oxide layer thickness; it is widely used for colour coding in medical devices.