In the design and use of machine tools and tools, it is necessary to apply the cutting principles of cutting force, cutting temperature and cutting tool performance data. For example, when determining the basic parameters such as high torque and rigidity of the spindle of the machine tool, the data of the cutting force should be applied; In the development of new materials with high cutting performance, it is necessary to master the law of tool wear and damage; When analyzing the influence of thermal deformation on machining precision, the cutting temperature and its distribution should be studied. In the automatic production line and digital control machine tool, in order to make the machine tool can work normally and stably, and even realize unmanned operation, it is necessary to apply the research results on chip formation and control, and realize the automatic compensation of tool wear and automatic alarm of tool damage in the processing. 

To this end, various countries have developed a wide variety of online detection tool wear and damage sensors, most of which use cutting force or torque, cutting temperature, tool wear as sensing signals. In addition, in order to make full use of machine tools, improve machining economy and develop computer-aided manufacturing (CAM), it is often necessary to apply optimization data such as cutting conditions, tool geometry and tool life. Therefore, the principle of metal cutting is increasingly widely used in production, countries have accumulated a large number of cutting data through cutting tests or field collection, and mathematical models are used to describe the relationship between tool life, cutting force, power and machining surface roughness equal to cutting conditions, and then stored in computers to establish metal cutting databases or compiled into cutting data manuals, for users check.