# Distribution and Prediction of Incremental Cutter Flank Wear in High-Efficiency Milling
## 1 Introduction  
The friction generated by a high-efficiency milling cutter in the cutting process directly affects the tool's wear. This phenomenon is inevitable in the machining process and is affected by many factors [1; 2]. With improvements to the technical requirements made, more complex and difficult-to-machine composite materials are used in the aviation industry, which have good heat resistance and oxidation resistance. In its machining process, workpiece loss is fast, with a short service life [3; 4]. The wear of milling cutter teeth will affect the service life of milling cutters and limit the further development and application of high-efficiency cutting technology. Therefore, it is necessary to conduct in-depth research on the friction behavior of high-efficiency milling cutters and the prediction of tool tooth wear. At present, the main bottleneck in the field of machining is tool wear and the resulting shortening of tool life, which ultimately leads to low machining accuracy and low productivity [5]. Tool life is basically defined as the time required to reach a predetermined flank wear width, and tool condition and life prediction are the most relevant factors in identifying the state of tool wear [6; 7]. The judgment of tool wear and breakage in existing industrial applications is mainly based on experience through passive shutdown and manual inspection [8]. If the tool is replaced too early, it will directly reduce processing efficiency and increase manufacturing costs. In recent years, in order to give full play to themaximum cutting performance of a tool, an important development trend has been the use of on line real-time monitoring technology to study tool wear and damage, which is very important for the realization of CNC machining, with few people (or even none) attending the tool, or with one person attending multiple machines [9]. There are three important time stages in the evolution of typical tool wear failure within the cutting process: the initial stage of wear, the stable wear stage, and the accelerated damage stage [10]. In the early 20 th century, American engineer [PERSON] developed a model to monitor tool wear and found that the factors affecting tool wear are cutting speed > feed > cutting depth [11]. In addition, domestic and foreign scholars have carried out a lot of research on other factors that cause tool wear. [PERSON] [12] studied tool wear from the perspective of direct and indirect methods and analyzed and summarized the problem of tool wear monitoring in the cutting process in detail. A total of 87% of the literature proposes a multisensor method for monitoring typical process parameters, such as tool force, vibration, and acoustic emission signals. [PERSON] et al. [13] carried out external ultrasonic vibration excitation on a workpiece and evaluated surface morphology quality under different tool wear conditions from the perspective of workpiece dynamics and kinematics. [PERSON] et al. [14] studied the effect of different tool coating materials on tool tooth wear through a large number of cutting experiments. [PERSON] et al. [15] showed that the cutting load caused by the superstress state during the cutting process affected the early failure of the coating and further showed that cutting could cause tool friction and wear. [PERSON] et al. [16] analyzed and summarized the problem of tool condition monitoring from the perspective of different processing methods. [PERSON] et al. [17] considered five parameters: workpiece size, radius, cutting allowance, cutting depth, and cutting angle to study the influence of the contact area of cutter and workpiece on tool wear and concluded that the cutting depth and cutting angle have the greatest influence on tool wear. [PERSON] and [PERSON] [18] studied the influence of different workpiece inclination angles on tool wear.