In the machining of CNC parts, cutting force is a factor that can not be ignored, which directly affects the machining accuracy, surface quality and tool life. In order to avoid the adverse effects of cutting forces on parts, the following measures can be taken:
First, optimize cutting parameters
Cutting speed: Select a reasonable cutting speed, not only to ensure efficient processing, but also to control the service life of the tool. For aluminum machining, the cutting speed is usually higher than that of other metals (such as steel), and the recommended cutting speed range is 200-600 m/min.
Feed speed: Feed speed directly affects machining efficiency and surface quality. The commonly used feed speed range is 1000-3000 mm/min. Too high feed speed will increase the cutting force, may lead to workpiece deformation or surface roughness; Too low a speed will reduce the processing efficiency. Therefore, the feed speed needs to be adjusted according to the cutting speed, cutting depth and workpiece material.
Depth of cutting: The depth of cutting is the thickness of the material removed from the surface of the workpiece each time the tool cuts. Generally, the cutting depth of aluminum ranges from 0.5 to 5 mm. The greater the cutting depth, the greater the load of the tool, easy to produce vibration and tool wear. If the cutting depth is too small, the processing efficiency will be reduced. Therefore, the depth of cutting needs to match the feed speed and cutting speed.
Second, choose the right tool
Tool material: Select the appropriate tool material according to the characteristics of the processing material. For example, carbide cutting tools are suitable for high-efficiency aluminum processing because of their high wear resistance.
Tool geometry parameters: The geometry of the tool (such as front Angle, back Angle) has an important impact on the machining effect. Choosing a sharp tool can reduce cutting force and vibration. For aluminum processing, a tool with a larger front Angle can reduce cutting force and improve surface quality.
Tool wear: Check the wear of the tool regularly, and replace the tool with serious wear in time to maintain the stability of the cutting force.
Third, improve cutting conditions
The use of cutting fluid: The rational use of cutting fluid can reduce cutting force, reduce tool wear and improve the quality of the machined surface. Cutting oil based on lubrication can significantly reduce cutting force.
Fixture design: Design a reasonable fixture to provide adequate support and reduce vibration and deformation during cutting. The clamping force of the fixture should act in the direction of the workpiece rigidity, and minimize the clamping force under the premise of ensuring that the workpiece is not loose.
Symmetrical processing: For large thin-walled parts, symmetrical processing can avoid deformation caused by heat concentration and uneven force.
Fourth, process optimization
Separate rough and finish machining: Rough and finish machining are carried out separately to reduce the impact of cutting force and cutting heat on the accuracy of parts. The roughing process mainly removes most of the machining allowance, and the machining accuracy is not high. Precision and high quality are pursued in finishing.
Heat treatment process: Arrange appropriate heat treatment process (such as low temperature annealing or aging treatment) after roughing and before finishing to remove internal stress and reduce part deformation.
In summary, by optimizing cutting parameters, selecting the right tool, improving cutting conditions and process optimization measures, we can effectively avoid the adverse effects of cutting force on CNC parts processing, and improve processing accuracy and surface quality.
