Titanium alloy difficult processing countermeasures

1. Cooling
Use coolant to reduce cutting temperature. In general, insoluble oil coolant is suitable for low-speed and heavy-duty cutting, and soluble cutting coolant is suitable for high-speed cutting.

In addition, the low temperature cutting method can be used, such as the use of liquid nitrogen (-180 ° C) or liquid CO2 (-76 ° C) as the cutting fluid, which can effectively reduce the temperature of the cutting zone, improve the quality of the machining surface, and extend the tool life.

2. Choose the right tool
Choosing the right cutting tool can significantly improve the processing efficiency. Because the heat of titanium alloy is mainly dissipated by the cutting edge and the coolant, rather than by the chip as in steel, the tiny part of the cutting edge needs to withstand great thermal and mechanical stress. Keeping the cutting edge sharp reduces the cutting force.

In addition, grinding technology with polished grooves and indexable blades with high positive angles also help to reduce cutting pressure.

If necessary, coating tools can also be used to reduce the viscosity of the alloy and break up excessive long chips. This not only reduces friction during chip removal, but also helps control the heat generated during processing.

3. Constant feed or increase feed rate
Titanium alloys are prone to hardening during processing, that is, when cutting, the hardness of titanium alloys will increase, which will accelerate the wear of tools. Therefore, maintaining a constant feed is essential to minimize work hardening.

Of course, if the equipment performance allows, you can try to increase the feed rate. Doing so reduces the amount of time the tool spends in the machining area, thereby reducing the chance of heat buildup and work hardening.

4. Reduce the cutting speed
Control the heat release and use 1/3 of the steel cutting speed or less for titanium alloy processing.

5. Replace the tool according to the process
When machining titanium alloys, the life of ceramic, titanium carbide and titanium nitride coated tools is relatively short. Generally, for large quantities of titanium alloy processing, hard steel tools are the first choice; For small batch processing, the use of high-speed carbide tools is more suitable.

At present, ultrasonic processing technology is being developed to extend the service life of the tool by reducing the contact time between the tool and the workpiece.

6. The use of high-rigidity machine tools
High rigidity machine tools are essential for successful machining of titanium alloys. The ideal titanium alloy milling machine must be rigid and the spindle can operate at low speed and high torque to absorb vibration and reduce chatter during cutting.

7. Clean regularly
Clean the processing equipment and tools regularly to prevent debris deposition and affect the processing effect.