How to Drill Titanium?

Titanium is a kind of hard but light metal, widely used in aerospace, medical and high-end manufacturing. Titanium is very hard to process, especially it will be a calorification and worn drill bit when you drill it. While this blog would be guide you how to drill titanium rightly for different titanium grades, then make drilling titanium much easier.

Steps to Drill Titanium

Material Confirmation

First need to confirm material, it is pure titanium or alloy titanium, the last one is stronger.

Then check the fixed state of the workpiece to avoid vibration.

Choose Tool

The Material of Bit

Hard alloy drill bit( first choice, such as tungsten and cobalt types).

Cobalt high-speed steel (HSS-Co) (suitable for small-batch processing).

Diamond-coated drill bit (high precision requirements)

Geometric Parameters

Top Angle: 135° to 140° (to reduce cutting resistance)

Helix Angle: 30° to 40° (conducive to chip removal)

Sharp cutting edge (to avoid work hardening)

Cooling and Lubrication

Water-soluble cutting fluid or high-pressure oil cooling (such as vulcanized oil) must be used.

For deep hole processing, it is recommended to use internally cooled drill bits (with coolant reaching the drill tip directly).

Positioning and Drilling

Mark with a center punch or positioning drill to prevent the drill bit from sliding.

Reduce the initial feed rate by 50% (to avoid chipping of the drill bit).

Cutting Parameter Setting

Parameter	Pure Titanium(Gr1,Gr2)	Alloy Titanium(Ti6Al4V)
Rotational speed(RPM)	30-50 m/min	20-40 m/min
Feed rate	0.05-0.1 mm/rev	0.02-0.08 mm/rev

 

Drilling Operation

Continuous cutting: keeping feed rate, avoid pauses (to prevent hardening).

Control Chip Removal

Remove the tool and chips at a depth of 2 to 3 times the hole diameter for each drill.

Use compressed air to assist in chip removal (especially for deep holes).

Monitor Status

The chips should be silver and short-rolled. If the color becomes blue or purple, that means too hot.

Drilling Titanium Speeds and Feeds

Drilling Parameters for Pure Titanium & Titanium Alloy

Material	Bit Type	Vc m/min	f mm/rev	Cooling
Pure Titanium	HSS	15 – 25	0.03 – 0.10	Cutting Fluid
	Carbide	40 – 70	0.06 – 0.15	High-Pressure Coolant
Titanium Alloy	HSS	10 – 20	0.02 – 0.08	Cutting Fluid or MQL
	Carbide	30 – 60	0.05 – 0.15	High-Pressure or Cryogenic Cooling

 

4 Ways of Drilling Titanium

The way of drill titanium depends on material shape, thickness and processing requirements, below are common 4 ways.

Ordinary drill bit

Applicable conditions: Titanium plate(1~10mm), thin titanium bar(Diameter＜10mm).

Pecking drill

Applicable conditions: deep hole, titanium ingot and thick titanium bar.

Laser drill

Applicable conditions: ultra-thin titanium foil(＜1mm), or requirements high mini hole(like medical implant)

Electrical discharge machining

Applicable conditions: super hard alloy titanium(like Ti-6Al-4V), or non-circular holes (like square holes, irregular grooves).

How to Drill Titanium by Hand?

Drilling titanium by hand(especially alloy titanium), needs special attention technique, because titanium’s characteristics like low thermal conductivity, high chemical reactivity and easy work hardening will make the ordinary drilling methods lose efficacy.

Frist choose hard alloy drill bit(such as tungsten-cobalt type YG8)or cobalt high-speed steel drill bits (SS-CO), ordinary high-speed steel drill bits will wear out rapidly.

Then, use the center punch to strike out a pit at the drilling position (to prevent the drill bit from slipping). First, drill the guide hole with a small-diameter drill bit (like 2mm), and then gradually expand the hole (reduce the pressure of the larger drill bit).

Attention

Fire prevention: Titanium chips are flammable. Keep away from sparks or high temperatures.

Protection: Wear anti-cut gloves (titanium chips are as sharp as blades) and goggles to prevent flying chips.

Workpiece fixation: It must be clamped with a bench vise. Holding it by hand is very likely to cause loss of control.

Key points

“Low speed, frequent tool retraction, strong cooling, and stable feed”

Follow this operation and you can drill titanium smoothly even by hand!

Best Drill Bit for Titanium

Hard alloy drill bit (solid hard alloy)

Diamond-like carbon coated (DLC) carbide drill bit

Titanium aluminum nitrogen coated (TiAlN) drill bit

Cobalt high-speed steel (HSS-Co) drill bit

Internal cooling deep hole drilling

Then what’s the super drill bits?

Nanocrystalline diamond-coated carbide drill bit

Ultrafine-grained cemented carbide internally cooled drill bit

Intelligent variable parameter drill bit

Difficulties in Titanium Drilling 

Why is drilling titanium so hard?

When you drilling titanium;

It’s like cutting” gummy candy”, titanium chips are long and sticky, and easy to get entangled with the drill bit.

It’s like being “simmered” : the heat can’t escape, and the drill bit seems to be working in a furnace.

It’s like drilling a “spring” : Titanium undergoes elastic deformation, and if you’re not careful, the hole will be drilled off course.

The four difficulties of drilling titanium

1. Poor heat conduction → The drill bit is prone to burning out
2. High chemical reactivity → Prone to “sticking to the knife”
3. Low elastic modulus → Prone to “tool deflection”
4. Work hardening → Harder the more you drill

Conclusion

The difficulties of drill titanium mainly from poor heat dissipation, sticky to the knife, and high elasticity.

In contrast, the drilling difficulty of aluminium, steel and copper is much lower.

But as long as the correct methods are mastered, titanium can also be successfully conquered!

FAQ

Q: What’s the price of drill titanium?

A: You can click here to check our price for drill titanium.

Q: Is it hard to turning titanium?

A: Yes, it’s hard to turning titanium. Because it’s low thermal conductivity, high chemical reactivity, high strength, low elastic modulus, and tendency to work hardening.

Q: Is it hard to cutting titanium?

A: Yes, titanium is very hard to cutting. Because it’s prone to sticking to the knife, has poor heat dissipation and high hardness.