3 Axis CNC Machining Titanium

What makes titanium behave differently under the tool?

Titanium cuts at a low speed not because it is hard but because it is a poor conductor and chemically reactive at cutting temperature. Heat concentrates in the tool tip rather than the chip, and at temperature the alloy tends to weld to the cutting edge, which is what destroys tools. The response is low cutting speed, high feed, sharp tools, and generous, well-directed coolant. The opposite of the intuition built up on aluminium. Material cost and tool cost are both high, so the biggest lever on price is design: removing unnecessary pocket depth can cut cycle time more than any process change.

Choosing a grade within titanium

Commercially pure (CP) grades and the alpha-beta alloy Ti-6Al-4V are what come up in practice. Grade selection is settled by the service environment, corrosion, strength, or temperature, and only then by machinability.

Grade (typical)	Type	Where it is used	Machining note
Grade 1 / 2 (CP)	Commercially pure	Corrosion service, formability	Softer, gummy; rigid setup, sharp tools
Grade 5 (Ti-6Al-4V)	Alpha-beta alloy	Aerospace, medical, high strength-to-weight	The workhorse; low speed, high feed, good coolant
Grade 7	CP + palladium	Aggressive corrosion	Like CP, with better resistance
Grade 23 (Ti-6Al-4V ELI)	Extra-low interstitial	Medical implants	Machined like Grade 5; biocompatible spec
Grade 9 (Ti-3Al-2.5V)	Alpha-beta	Tubing, moderate strength	Slightly easier than Grade 5

These are typical family behaviours. Aerospace and medical work carries a heavier traceability and qualification burden, and the grade is confirmed against the mill certificate before the first cut.

The cutting mechanism, and what it demands

The three properties that make titanium difficult are low thermal conductivity, a tendency to weld to the edge at temperature, and a low modulus that lets the part deflect under the cutting force. The machining response is therefore: modest surface speed, a positive feed that keeps shearing, the sharpest practical edge, rigid workholding so the part cannot spring, and coolant that actually reaches the shear zone. Climb milling reduces the rubbing dwell that heats the edge. The mistake is to treat it like steel and run it hot — the tool fails quickly.

DFM tips specific to titanium

• Minimise stock removal. cycle time scales with volume removed and titanium removes slowly, so thinner webs and shallower pockets save twice (time and tooling).
• Support thin features. the low modulus means a thin wall deflects under cut; reduce depth of cut or support it rather than forcing tolerance.
• Rigid workholding — deflection, not hardness, is usually what limits the finish. A solid clamp beats a fancy tool.
• Internal corner radius — match it to a real cutter; small tools chatter and fail fast in titanium.
• State the spec. name ASTM B348 or AMS grade on the drawing; the shop verifies composition by XRF.

Dimensional behaviour

The low modulus means a titanium part deflects more under the same cutting force than steel, so thin features need support or a reduced depth of cut. Thermal expansion is low, which helps once the part is finished and cool. The general rule is that a tolerance is held by the process, not by the machine: where a feature is tight, the finishing pass is separated from roughing, the part is allowed to stabilise, and the measurement is taken at a controlled temperature.

Finishing and surface treatment

As-machined finishes are usually acceptable; where an anodised or bead-blasted surface is specified, the machining allowance must account for it. Titanium can be coloured by anodising in oxide-thickness bands, and passivation is less about corrosion (it is already corrosion-resistant) than about removing surface contamination. You specify finishing on the drawing, not assume it at the end.

What titanium does to tooling and cycle time

Heat concentrates in the tool tip rather than the chip, and at temperature the alloy tends to weld to the cutting edge, which is what destroys tools. The lever that matters most for you is usually design rather than process: pocket depth, corner radius, and wall thickness change cycle time more than any tooling choice, because they determine the tool that can be used and therefore how much material can be removed per minute.

Tolerance and lead time±0.003 mm on CNC milling, ±0.002 mm on CNC turning; ±0.002 mm where precision grinding or wire EDM is used, fixed for each feature at the quote. Because titanium is cut slowly, lead time is dominated by cycle time more than by setup, so the highest-value design change is removing stock that does nothing, thinner webs, shallower pockets, fewer deep features.

How much of the floor is in this family?

Total machine count is not the question, the question is how many machines sit in the family that makes your part, because that is the queue your part waits in. The floor runs a floor of 100-plus machines: 50+ three-axis centres for prismatic work, 20+ four-axis, 20+ five-axis, 25+ turning and mill-turn centres, Swiss-type lathes for long slender parts, precision grinding and wire EDM for the tightest features. The spare capacity in that family is what lets a part re-route rather than queue when a machine is pulled for service.

What the certificates cover, line by line

Three certificates, each with a number you can check with the registrar:

Standard	Certificate number	Scope note
ISO 9001:2015	116024/A/0001/UK/En	Quality management system
IATF 16949:2016	131941/A/0001/SM/En	Automotive QMS — excludes clause 8.3 product design
ISO 14001:2015	116024/B/0001/UK/En	Environmental management system

The IATF 16949 certificate excludes clause 8.3 (product design). That is normal for a build-to-print manufacturer and it is stated here rather than left for an auditor to discover: the shop builds to the design you supply, it does not originate the design.

Which entity is responsible for the work?

Dongguan Zhuohang Ltd, Registration No. 91441900MA4UWT6X39, in operation since 2005. You can verify a Chinese manufacturer through the National Enterprise Credit Information Publicity System using that 18-character code; a trading company's licence will show a trading scope rather than a manufacturing one, and an office rather than a plant.

What the extra axes actually buy

The axis count is about setups, not precision. A 3-axis machine cuts from one direction, so a part with features on several faces needs to be re-fixtured between operations - and every re-fixture introduces a small error. A 4-axis machine adds rotation, and a 5-axis machine can reach five sides in one setup, so the features on several faces stay in the same coordinate frame and line up. For a part that is a prismatic block, 3-axis is enough and cheapest; for a part with angled or multi-face features, the extra axes buy accuracy and fewer operations. You choose the axis count for the geometry, not by habit.

How to read an axis-based quote

If a part genuinely needs 5-axis work, the quote reflects one setup and tighter feature relationships; if a shop puts a 3-axis part on a 5-axis machine and charges for it, you are paying for capability the geometry does not use. This floor runs 3-, 4- and 5-axis machines including the Mazak VARIAXIS I-600 five-axis and the INTEGREX I-250H S mill-turn, at ±0.003 mm milled. Contact Felipe Iglesias at [email protected] or +86 13126536955 with the drawing and ask which axis count the geometry actually justifies.

De-risking a first order

Start with a handful of parts to confirm the routing and the tolerance, then scale. The same machines, the same inspection bench and the same certificate numbers apply to a single piece and a production run alike, so a small first batch is the proof that a large one will hold the same numbers.

What this shop actually runs

Capability evidence should come as specifics, not slogans. Behind this guide is a 6,800 m2 plant in Dongguan, China running 100+ CNC machines with 100+ staff. The machine list by category:

• 5-axis machining centres (10+) - Mazak VARIAXIS I-600 (510/910/510 mm travel, 12,000 rpm, 22 kW, 71.6 N·m, 30-tool BT40) and Mazak INTEGREX I-250H S (B-axis 0.0001°, 24 kW, 124 N·m, 38-tool HSK-A63). Cut on compound-angle parts, single-setup multi-face prismatic work, and aerospace fittings where datum transfer loss is unacceptable.
• 3-axis / 4-axis machining centres (50+) - Brother SPEEDIO S500Z2N / S700Z2N (10,000 rpm, 14/21-tool ATC, 0.7 s tool-to-tool, Z-axis 2.2 G) and Mazak VCE-430A L / VCE-570C L (10,000 rpm, 118 N·m, 24-tool ATC). Cut on prismatic parts, plates, brackets, housings.
• Swiss-type turning centres (10+) - Citizen Cincom A20-3F7 (Φ20 mm, 10,000 rpm), TSUGAMI B0206-III / B0205-III (Φ20 mm, 0.1 µm), STAR SR-32JII / SR-32J Type N (Φ32 mm, 8,000 rpm). Cut on long, slender rotational parts at ±0.002 mm.
• CNC turning centres (20+) - HEADMAN T70M/1250 (720 mm swing, 117 mm bore, 3,000 rpm, BMT75 12-station turret). Cut on shafts, bushings, flanges up to ±0.002 mm.
• Wire EDM (5+) - Sodick AQ535L (550/350/300 mm travel, ±20° taper, 800 kg workpiece). Cut on hardened tool steel, internal splines, sharp internal corners that milling cannot reach.
• Inspection: Hexagon CMM + 20+ gauges - Hexagon CMM for coordinate measurement, plus vision system, profilometer, hardness tester, coating thickness gauge, XRF for material verification. The 10:1 rule (gauge 10x more accurate than the band) is applied to every feature.
• Machine highlights - VARIAXIS I-600: one-setup multi-face 5-axis + MAZA-CHECK auto-calibration; INTEGREX I-250H S: DONE-IN-ONE mill-turn, B-axis 0.0001° + Ai thermal shield; SPEEDIO S500Z2N / S700Z2N: Z-axis 2.2 G + 0.7 s ATC; Swiss-type: guide-bush switchable + 0.1 µm resolution.

Tolerance: ±0.003 mm CNC milling / ±0.002 mm CNC turning / ±0.002 mm grinding and wire EDM. Capability: Ppk >= 1.67 initial on key characteristics, Cpk >= 1.33 ongoing.

Certificates: ISO 9001:2015 (116024/A/0001/UK/En), IATF 16949:2016 (131941/A/0001/SM/En, with design clause 8.3 excluded, stated openly) and ISO 14001:2015 (116024/B/0001/UK/En), issued to Dongguan Zhuohang Ltd, registration 91441900MA4UWT6X39, founded 2005.

Where we ship: Austria, Belgium, the Czech Republic, Denmark, France, Germany, Greece, Hungary, Ireland, Italy, the Netherlands, Spain, Sweden and the United Kingdom in Europe; Brazil, Canada, Mexico and the United States in the Americas; China, Israel, Japan, Singapore and Sri Lanka in Asia; Australia and New Zealand in Oceania; and South Africa in Africa — plus other countries and regions worldwide, shipped from our base in Dongguan, China.

Contact: Felipe Iglesias, [email protected], +86 13126536955.

Frequently Asked Questions

Standards referenced on this page

• ASTM B348/B348M-21 — Standard Specification for Titanium and Titanium Alloy Bars and Billets
• ASTM B211/B211M-19 — Standard Specification for Aluminum-Alloy Rolled or Cold Finished Bar, Rod, and Wire
• ISO 9001 — Quality management systems — Requirements