Problems that should be paid attention to in difficult machining materials

The cutting process is roughly divided into turning, milling, and centering-based cutting (drilling, end milling of end mills, etc.). The influence of cutting heat on the cutting edge of these cutting processes is also different. Turning is a kind of continuous cutting, and there is no obvious change in the cutting force on the cutting edge. The cutting heat continuously acts on the cutting edge; milling is a kind of intermittent cutting. The cutting force acts on the cutting edge intermittently, and vibration will occur during cutting. The heat effect on the cutting edge is alternated between heating during cutting and cooling during non-cutting, and the total heat is less than when turning.

The cutting heat during milling is an intermittent heating phenomenon, and the cutter teeth are cooled when they are not cutting, which will help extend the life of the tool. The Japan Institute of Physics and Chemistry conducted a comparative test on the tool life of turning and milling. The tools used for milling are ball end mills and turning are general turning tools. Both are processed in the same material and cutting conditions (due to different cutting methods, cutting The depth, feed rate, cutting speed, etc. can only be roughly the same) and the cutting comparison test under the same environmental conditions. The results show that milling is more beneficial to prolong the tool life.

When cutting with tools such as drills and ball end mills with a center edge (ie, cutting speed = 0 m/min), the tool life near the center edge is often reduced, but it is still stronger than when turning. When cutting difficult materials, the cutting edge is greatly affected by heat, which often reduces the tool life. If the cutting method is milling, the tool life will be relatively long. However, difficult-to-machine materials cannot be all milled from beginning to end, and there will always be times when turning or drilling is needed in the middle. Therefore, corresponding technical measures should be taken for different cutting methods to improve processing efficiency.