China CNC Titanium Processing Guide

Titanium sits in an awkward place for machining. It holds roughly 60% of the stiffness of steel but carries loads at half the density, so thin ribs and long slender features deflect before the cutter is even loaded. Thermal conductivity is low, around 7 W/m·K for Ti-6Al-4V. Heat generated at the cutting edge has nowhere to go except into the tool and the part surface.

That heat concentration is what kills tools. Carbide edges reach 1,000 °C in a cut that would run cool in 6061 aluminum. Above roughly 600 °C titanium starts absorbing oxygen and nitrogen from the air, and the resulting alpha case is hard and brittle. Cut through it and the surface layer cracks under fatigue.

There is also the chemical side. Titanium welds itself to cutting tool materials under pressure, so a dull edge grabs instead of shears. Built-up edge grows fast, then breaks off and takes a chip of the workpiece with it. Rubbing, not cutting, is the usual failure mode on a badly programmed titanium job.

None of this makes titanium unmachinable. It makes the process window narrow. Feed per tooth, radial engagement, coolant pressure and tool coating all have to line up. Get them right and TC4 cuts predictably at 40–60 m/min surface speed.

Most titanium work that lands on a Chinese CNC floor is one of three grades. Commercially pure TA1 and TA2 are soft, weld easily and go into chemical and marine parts. TC4, known in the West as Ti-6Al-4V or Grade 5, is the workhorse for aerospace brackets, medical instruments and motorsport components.

Grade 5 responds to heat treatment and reaches about 950 MPa tensile. That strength is the reason it is specified, and also the reason it is slow to cut. Grades 2 and 5 together cover the large majority of drawings we quote.

Grade 23, the ELI version of Ti-6Al-4V, turns up in implants where fracture toughness and low interstitial content matter. It machines much like Grade 5 but costs more and needs tighter material traceability. Ask for the mill certificate before the first cut, not after.

If your part only needs corrosion resistance and not high strength, say so on the drawing. Substituting TA2 for TC4 can cut cycle time by a third and reduce tool wear sharply. We flag this during DFM review when the load case allows it.

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  TA1 / TA2Commercially pure. Easy to cut, good corrosion resistance, lower strength.
• 2
  TC4 (Grade 5)Ti-6Al-4V. Heat treatable to about 950 MPa. The default structural grade.
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  TC4 ELI (Grade 23)Lower interstitials, higher toughness. Medical implants, traceability required.

A three-axis titanium job usually means several setups. Every setup is a chance to lose position and a chance to load the part onto a fixture that flexes. Five-axis work cuts most of that away. On a simultaneous five-axis center, the tool reaches the back side of a bracket without the operator unclamping it.

The bigger gain is chip evacuation and tool engagement. Tilting the tool axis lets the cutter exit the cut cleanly instead of rubbing at the bottom of a pocket. On titanium, that single change can double tool life. Contouring a curved surface with the tool tip also spreads wear across the full flute length.

GreatLight runs 16 simultaneous five-axis machining centers, alongside 12 four-axis mills and 27 three-axis machines. Five-axis travel reaches 4,000 × 400 × 150 mm for long parts, with 750 × 1,150 × 550 mm and 600 × 600 × 600 mm envelopes for mid-size work. Compact cells cover 500 × 500 × 450 mm. A Ø400 mm rotary table handles round parts that need indexed features on several faces.

Not every titanium part belongs on a five-axis machine. A simple plate with drilled holes is cheaper on a three-axis mill, and moving it to a five-axis cell only adds hourly rate. The decision should follow geometry, not the machine list.

High-pressure through-spindle coolant is not optional on titanium. Delivering 70 bar or more at the cutting edge breaks the chip, clears heat and stops the recut that dulls edges. Flood coolant alone works on shallow cuts but loses control once a tool goes deeper than two diameters.

Tooling follows the same logic. Uncoated fine-grain carbide with a sharp edge is a common choice for finishing. For roughing, AlTiN or AlCrN coatings resist the heat, but the edge geometry has to stay sharp. Avoid the same high-helix geometry you would use on aluminum; it pulls the part into the cutter.

Parameters vary with the rigidity of the setup. Roughing a solid TC4 block at 40–50 m/min with 0.1–0.15 mm feed per tooth is a workable starting point. Finishing runs faster, 60–80 m/min, with light radial engagement. Climb milling is standard.

Tolerance is where the plan gets tested. GreatLight holds ±0.005 mm (±0.0002 in) on titanium features, with a 99.99% qualification rate across inspected parts. That number only holds when the fixture is stiff and the stock has been stress-relieved before the final pass.

Titanium stock is expensive, and so is the machine time. A Chinese supplier working from Dongguan or Singapore can spread tooling and programming cost across a wider machine base, which matters on low-volume runs that still need five-axis capability. That is the practical reason buyers move titanium work here.

The second reason is turnaround. GreatLight quotes and returns a free DFM analysis within 12 hours, and production can start within 24 hours of approval. Titanium parts typically ship in 3–5 days. Historical late-delivery probability sits below 2%, which is the number that matters when an aerospace bracket is holding up an assembly.

Certification coverage matters more than price on regulated parts. The plants hold ISO 9001:2015, IATF 16949:2016, ISO 13485:2016 and ISO 27001:2022. Medical and automotive titanium work can be routed through the relevant system without a separate supplier audit.

There is no minimum order quantity. One prototype and a 10,000-part run go through the same quoting path. For engineers still validating a design, that removes the usual penalty for small titanium batches.

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  Three plants7,600 m² in total, Dongguan and Singapore, 150 technicians.
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  127 CNC machines16 five-axis, 12 four-axis, 27 three-axis, 16 mill-turn centers.
• 3
  InspectionRaw material check, in-process monitoring, final inspection, 100% before shipment.
• 4
  ConfidentialitySecure uploads; NDA available on request before drawings are shared.