Machining titanium technology
Machining technology of titanium parts
1. Turning titanium parts
Turning titanium alloy products can easily obtain better surface roughness, and the work hardening is not serious, but the cutting temperature is high and the tool wears quickly. In view of these characteristics, the following measures are mainly taken in terms of tools and cutting parameters:
Several Correct Choices for Milling Thin Parts
High-speed CNC machining of titanium alloy parts
In milling, an important characteristic of titanium alloys is extremely poor thermal conductivity. Due to the high strength and low thermal conductivity of titanium alloy materials, extremely high cutting heat (up to 1200°C if not controlled) is generated during processing. The heat is not discharged with the chips or absorbed by the workpiece, but is concentrated on the CNC cutting edge. Such high heat will greatly shorten tool life.
Examples of high-speed milling of titanium parts
Machining characteristics of titanium alloy
Turning and milling are particularly difficult when the hardness of titanium alloy is greater than HB350. When the hardness of titanium is less than HB300, the sticking phenomenon is likely to occur, and it is also difficult to cnc cutting. But the hardness of titanium alloy is only one aspect that is difficult to cut.
How to choose the tool material for CNC machining of titanium?
CNC machining of titanium alloys should start from two aspects: reducing cutting temperature and reducing adhesion. Select tool materials with high thermal hardness, high bending strength, good thermal conductivity, and poor affinity with titanium alloys. YG cemented carbide is more suitable. Due to the poor heat resistance of high-speed steel, tools made of cemented carbide should be used as much as possible. Commonly used cemented carbide tool materials include YG8, YG3, YG6X, YG6A, 813, 643, YS2T and YD15.
Set tool parameters for CNC machining titanium
Set the geometric parameters of turning and milling titanium tools to improve the product quality of titanium alloy parts. Products are delivered quickly and on time.
(1) The rake angle of the tool γ0: The contact length between titanium alloy chips and the rake face is short. When the rake angle is small, the contact area of the chip can be increased, so that the cutting heat and cutting force are not excessively concentrated near the cutting edge. Improve the heat dissipation conditions, and can strengthen the cutting edge and reduce the possibility of chipping. Turning titanium generally takes γ0=5°~15°.
Pay attention to the problem of machining titanium alloy
In the process of CNC turning and milling titanium alloy, the matters that should be paid attention to are:
(1) Due to the small modulus of elasticity of titanium alloy, the clamping deformation and force deformation of the workpiece during machining are large, which will reduce the processing accuracy of the workpiece; The clamping force should not be too large when the workpiece is installed, and auxiliary support can be added when necessary.
How to mill titanium?
When titanium alloy is milled at low speed in an inert gas medium, the milling deformation coefficient is greater than 1.0; But in the atmosphere, when the milling speed Vc=30 m/min, the chip deformation coefficient is less than 1.0. This is because titanium alloys have a great affinity for oxygen and nitrogen in the atmosphere during high-temperature milling.