3C Electronics Titanium Alloy (Ti-6Al-4V) Machining : Side Milling

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What makes Titanium Alloy difficult to machine?

The good ductility and work hardening properties of titanium alloys have brought serious concerns for the quality of hole wall and the positional precision of the drilling holes.  If the thrust force and torque are not well-controlled, the workpiece may suffer from displacement due to its ductile property.  Its hardened surface and entangled chips will also cause severe damages to both the quality of workpiece and its positional precision.  When it comes to higher aspect ratio (hole depth to diameter), it is going to be even more challenging to maintain the quality. 

The work hardening property of titanium alloys when it is heated has brought huge difficulties in drilling this material.  With the protective oxide layer on the surface of titanium alloys, the drills may lose their sharpness easily and even encounter risks of tool breakage.  Along with the entangled chips produced in the drilling process, not only the quality of workpiece is at stake, but also the tool life will be disastrously unstable.  The major challenge also lies in controlling the thrust force and torque in the drilling process.

 

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☑️ Titanium Alloy Machining Information

 

	Titanium Alloy Machining Information
Material	Titanium alloy (Ti-6Al-4V)
Feature	Ap 8mm, Ae 0.03mm
Process	Side milling
Ultrasonic Tool Holder	BT30-R01-10
Rotating Speed	16,000 ~ 20,000 rpm
Machine Tool Type	C type vertical machining center

 

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(Figure 1. ultrasonic-assisted side milling on Titanium Alloy workpiece)



(Figure 2. BT-30 ultrasonic toolholder was used on Titanium Alloy side milling)

 

HIT's Goal in Machining Titanium Alloy

The goal is to improve tool life under higher machining efficiency, while maintaining high surface quality which meets client's requirement.


 

Ultrasonic-Assisted Machining Titanium Alloy Results

 

Titanium Alloy Side Milling : Machining Efficiency

HIT's ultrasonic-assisted machining technology allowed to raise the cutting speed 3 times faster than that without ultrasonic, resulting in the increase in feed rate and machining efficiency.

 

Titanium Alloy Side Milling : Workpiece Quality

(Figure 3. comparison of titanium alloy side milling workpiece surface quality between HIT ultrasonic and non ultrasonic)
 

The high-frequency ultrasonic micro-vibration helped reduce the cutting heat, and achieved Sa < 0.3µm, which met with client's requirement on the surface quality.

 

Titanium Alloy Side Milling : Tool Life

(Figure 4. comparison of tool wear on the rake face between HIT ultrasonic and non ultrasonic machining on titanium alloy side milling)



(Figure 5. comparison of shape of chips between HIT ultrasonic and non ultrasonic machining on titanium alloy side milling)



(Figure 6. the Taylor Tool Life Curve shows the potential improved tool life with HIT ultrasonic machining on titanium alloy side milling)


The chips appeared to be larger and very difficult to break in conventional machining.  Along with the cutting heat, chips were repeatedly adhesive to tool's rake face, causing breakage on the tool blade.

The high-frequency micro-vibration of HIT's ultrasonic-assisted machining technology helped reduce cutting force and cutting heat, preventing the residual chips from stucking on the tool/workpiece.  It also allowed the chips to break easily with no entangled chips.


 

HIT Ultrasonic Machining Technology Achievements

🕜 Efficiency - 3 times faster than that without ultrasonic 
📈 Quality - cutting force/heat reduced, Sa < 0.3µm
⚙️ Tool Life - chips became smaller and easier to break, preventing residual chips from stucking on the tool

💰 With the enhanced machining efficiency and improved tool life, the production capacity can be greatly increased.



 

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Titanium Alloy Machining in Industry Application

Side milling Titanium Alloy is often applied in the 3C Electronics industry, Biomedical industry, and Automotive (electric vehicle) industry, especially for titanium bone plate, artificial joint, smart wearable device (Apple watch ultra bezel), and the underbody of Tesla Model S, etc.


Titanium alloy (Ti-6Al-4V) is rated approximately 41HRC for its hardness, which is not as hard compared to other metal alloys.  It offers a combination of lightweight, high strength, low density, good corrosion resistance and ductility.

The excellent material properties of titanium alloy, including lightweight, high strength, good corrosion resistance and good ductility, make it the prime choice for many fields of applications.  

Being non-toxic is also one of its excellent material attributes that allows it to be an ideal material for bone plates and artifical joints in biomedical industry.  Titanium alloy is also anti-fingerprint and resistant to stain, which makes it suitable for smartphone phone case or the bezel of smart wearable devices.  Its resistance to heat and high strength also allows it to be one of the perfect materials for the underbody of Tesla Model S to protect the battery from any roadside force or piercing. 

HIT's Ultrasonic Machining Module offers a comprehensive solution in machining these difficult-to-cut materials.  With the assistance of HIT's Ultrasonic Machining Technology, clients stopped worrying about poor surface quality and tool life.  Not only the surface quality and tool life can be improved, but the machining efficiency can also be greatly enhanced.  HIT assures its clients of matching up with their requirements and achieving even better outcomes!



💡 Learn more about Titanium Alloy Machining cases

• Titanium Alloy Machining : Micro-Drilling

💡 Introduction on Titanium Alloy Machining

• How to Drill Titanium : The Aerospace Fever in Titanium Drilling