Titanium CNC Machining: Ti-6Al-4V (TC4) and Grade 2 Parts
CHX Metal machines titanium parts in Grade 2, Grade 5 (Ti-6Al-4V / TC4), Grade 9 and Grade 23 on 220 CNC machines, holding plus or minus 0.005 mm on critical features. Titanium cuts at roughly one third the speed of aluminium, so prototypes run in 3 to 7 days and production in 7 to 15 days, from 1 piece.
Titanium is requested for three reasons: weight against strength, corrosion resistance, and biocompatibility. It is also the material that most often comes back from a cheap quote with a scrapped batch, because the cutting physics are unforgiving. This page sets out what we machine, how the process is controlled, and what to put on the drawing so the part is quoted the same way it will be made.
Titanium Grades We Machine
| Grade | Designation | Typical use |
|---|---|---|
| Grade 2 | Commercially pure Ti | Chemical process parts, marine hardware, heat exchanger components |
| Grade 5 | Ti-6Al-4V / TC4 | Structural brackets, drone airframes, fasteners, medical instruments |
| Grade 9 | Ti-3Al-2.5V | Tubing, hydraulic lines, parts needing formability with strength |
| Grade 23 | Ti-6Al-4V ELI | Implant-grade and low-temperature toughness applications |
Grade 5 is the workhorse: roughly twice the tensile strength of Grade 2 at similar density, and the grade most structural titanium parts are specified in. Grade 2 is chosen when corrosion resistance and ductility matter more than strength, and it machines more forgivingly.
Why Titanium Machines Slowly
Titanium's thermal conductivity is about 7 W/(m·K), roughly one twenty-fifth that of aluminium, so heat from the cut stays in the tool edge instead of leaving with the chip. The same low conductivity is why the part itself stays cool — and why an insert can fail in seconds if the cutting speed is set for aluminium. Three consequences follow:
- Cutting speed runs at roughly one third of the aluminium value for the same tool, with high feed maintained so the cut is a cut and not a rub.
- Coolant has to reach the edge, not the part. Through-tool coolant at high pressure is the difference between predictable tool life and a chipped insert halfway through a pocket.
- Work hardening means a dwell or a light pass on a hardened surface accelerates wear; we keep constant engagement instead of letting the cutter polish the wall.
Titanium also reacts with tool materials at temperature, so tooling is dedicated: cutters used on titanium never touch aluminium or steel, and the same rule applies to fixtures and to the cleaning station.
Cutting Strategy and Tooling
- Solid carbide tooling with sharp, high-rake geometry and a coating selected for titanium rather than for steel.
- Climb milling with constant depth of cut; trochoidal paths for deep pockets so the radial engagement stays small.
- Rigid, low-profile fixtures, because titanium's elasticity means any unsupported overhang rings and chatters.
- Program verification before the first cut: a simulated collision in a 20,000 line program is cheaper than a scrapped Grade 5 forging.
Tolerance, Surface Finish and Inspection
Critical features are machined to ±0.005 mm; general dimensions follow ISO 2768-m unless the drawing states otherwise. Surface finish is typically Ra 0.8 µm on functional faces, with better values available on request where a seal or a bearing seat requires it.
The parts that fail inspection are usually thin walls: a titanium wall under about 1 mm deflects under clamping and springs back after the cut, so we plan support, sequence the material removal, and measure after the part has relaxed rather than immediately off the machine. Every batch ships with CMM inspection records and a material certificate traceable to the mill heat number.
Finishing Options for Titanium
- Bead blasting for a uniform matte surface and removal of tool marks.
- Passivation to restore the oxide layer after machining and contamination from handling.
- Anodising for colour identification and wear indication on non-implant parts.
- Laser marking for part numbers and traceability codes.
Finishes are quoted as a separate line so the cost of each step is visible, and cosmetic criteria are agreed in writing before production rather than argued at inspection.
Typical Titanium Parts
- Drone and UAV airframe brackets, motor mounts and gimbal components.
- Medical instrument blanks, trial implants and surgical handles.
- Chemical pump housings, valve bodies and heat exchanger plates.
- Marine and offshore hardware exposed to chlorides.
- Motorsport and high-end consumer fasteners and structural fittings.
These are representative families rather than a closed list; the RFQ review confirms feasibility for any specific geometry.
DFM Rules for Titanium
- Keep wall thickness above 0.8 mm where the part has to hold tolerance without support; below that, expect extra fixtures and extra cost.
- Specify corner radii of at least 0.5 mm, preferably one third of the pocket depth, so a standard cutter can reach the corner.
- Avoid deep narrow slots: depth is limited to about four times the cutter diameter before deflection dominates.
- Put the tight tolerance on the functional datum faces only, not on the whole outline.
- State the finish and the cosmetic zone, so effort is spent on visible and sealing surfaces.
Send a STEP file and the drawing; DFM feedback arrives within 24 hours. Prototypes run in 3 to 7 days and production in 7 to 15 days, with finishing adding 3 to 7 days, from a minimum order of 1 piece.
Related Capability Pages
Frequently Asked Questions
Can you machine Ti-6Al-4V (TC4)? Yes. Grade 5 Ti-6Al-4V is the titanium grade we machine most often, alongside Grade 2, Grade 9 and Grade 23 ELI. Tooling and coolant strategy are dedicated to titanium, because the same cutter used on aluminium will fail on titanium.
Why is titanium more expensive to machine than aluminium? Cutting speed is roughly one third of the aluminium value, tool life is shorter, and fixtures must be stiffer. The material also costs more at the mill. The gap comes from time and tooling, not from a margin add-on.
What tolerance can you hold on titanium? ±0.005 mm on critical features such as bores, pilots and mating faces, with general dimensions to ISO 2768-m. Thin walls under about 1 mm need extra support and are quoted feature by feature.
Does titanium work-harden during machining? It does, which is why we keep constant cutter engagement and avoid dwelling in a cut. A light pass over an already hardened surface is the fastest way to destroy an insert, so the process plan prevents it rather than compensating afterwards.
What surface finish can titanium parts have? Ra 0.8 µm is typical on functional faces, with better values available where a seal or bearing seat requires it. Bead blasting, passivation, anodising and laser marking are the standard finishing routes.
What are the lead times for titanium parts? Prototypes in 3 to 7 days and production in 7 to 15 days, with finishing adding 3 to 7 days. Titanium is scheduled with tool-life allowance built in rather than quoted as if it cut like aluminium.
Do you supply material certificates? Yes. Every batch ships with a certificate traceable to the mill heat number, together with CMM inspection records for the critical dimensions.
Get a Quote → Upload your drawing or 3D model for a process plan and quotation within 24 hours.
