The hottest high-speed cutting should not only be

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High speed cutting should not only be measured by speed

productivity is closely related to cutting speed. The improvement of cutting speed can improve productivity. At the same time, the development of precision and ultra precision machining technology also requires the cutting speed of machine tools to be further improved

After the concept of high-speed machining was put forward, it has been widely used in industrial production only recently after long-term exploration, research and development. At present, the cutting speed has reached 3000m/min when processing steel parts, 3000m/min when processing cast iron, and 7000m/min when processing aluminum alloy, which is many times higher than the commonly used cutting speed. In addition to high-speed cutting, high-speed grinding technology has also entered the practical stage. The conventional grinding speed is 30 ~ 40m/s, while the ultra-high speed grinding speed has reached more than 150m/s. High speed cutting and grinding can not only greatly improve productivity, but also improve machining quality and machining surface quality

high speed cutting refers to cutting at a speed much higher than the conventional cutting speed. The traditional relationship between cutting speed and tool life is assumed to be linear, that is, the higher the speed of the tool, the faster the wear of the tool. In the first half of the 20th century, some researchers found that in some machining processes, after the cutting speed reached a certain value, the situation began to change, and the tool wear increased, but the speed continued to rise, beyond this range, it could return to normal, and the domestic demand would also reach 5.68 million kilometers. After long-term production practice, people realize that for a certain overloaded processed material, there may be a very ideal cutting condition in the area where the cutting speed is much higher than the current cutting speed, and the iron content of the lubricating oil is times related to the wear degree of the parts. Under this cutting condition, the productivity is high, the tool durability is long, and the cutting force is relatively small

the reduction of cutting force in high-speed cutting is the physical basis for the application and development of high-speed cutting technology. Some people think that the problem of why the cutting force will decrease when the speed is high to a certain extent is due to the softening of the workpiece material. This softening can be understood as the acceleration of cutting speed, the increase of cutting shear zone temperature and the reduction of material yield limit. Some researchers also believe that the energy required for cutting reaches an equilibrium point within a certain speed range. As the cutting speed is further accelerated, the cutting force decreases and remains unchanged after a certain speed, which is also called a strain gauge, and then may change slightly with the change of cutting momentum. However, these inferences cannot be accurately explained from the material deformation mechanism. Therefore, further research should examine whether the energy required to produce material deformation in cutting changes with the material deformation speed, and whether the material deformation mode is changed after the deformation speed (rheological speed) exceeds a certain limit value, so that the energy required for deformation is reduced. It is of great significance to determine this limit and seek the best cutting speed

how to define high speed cutting? At present, the general definition is 5 ~ 10 times the conventional cutting speed, which is called high-speed cutting. The author believes that under the premise of the establishment of Salomon theory, the cutting state when the cutting speed of a specific material reaches the limit speed should be called high-speed cutting. High-speed cutting is not only divided by speed, but closely related to the physical and mechanical properties of the material and the cutting state

although the practical technology of high-speed cutting has been formed at present, the research on the mechanism of high-speed cutting is still in the stage of experimental exploration, and the research on the basic theory is not mature. It is more scientific and reasonable to distinguish between conventional cutting and high-speed cutting from the changing state of physical and mechanical properties of materials in the cutting process, not just through the cutting speed. (end)

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