# The Simulation Analysis of Cutting Characteristics and Chip Formation Mechanism in Gear Skiving
## 1 Introduction  
The demand for gears in the electric vehicle reducer and robot reducer industries is enormous, and the requirements of gear processing precision are becoming increasingly stringent. The machining efficiency and accuracy of skiving are high, and they have unique advantages in the machining of internal gears and coupling gears, with good application prospects. However, the primary limiting application of gear skiving is the rapid wear of skiving tools [1; 2; 3].  
Currently, there is relatively little research on the fundamental causes of skiving tool wear, making it difficult to accurately reveal the stress patterns during skiving and the chip formation mechanism.  
This hinders the effective support of wear-resistant skiving tool and process design practices.  
[PERSON] et al. [4] used numerical penetration calculation methods to analyze the variation patterns of skiving chip thickness. [PERSON] et al. [5] studied the changes in tool working angles, cutting speed, and cutting thickness during the skiving process and examined tool wear characteristics through experimental methods. [PERSON] et al. [6] investigated the changes in tool working angles and cutting thickness by analyzing the causes of tool wear. [PERSON] et al. [7] used thermocouple methods to study the cutting heat during skiving and employed finite element methods to explore the chip formation mechanism. [PERSON] et al. [8] analyzed the influence of cutting parameters on chip shape using simulation cutting methods. [PERSON] et al. [4] combined simulation analysis and numerical calculations to study the variation patterns of skiving chip thickness. [PERSON] et al. [9] proposed a skiving method along the gear profile, where the skiving tool completes the gear slot processing through multiple radial feedings to improve tool wear.  
[PERSON] et al. [10] studied the impact of the tool edge radius on tool life in skiving. In China, theoretical and experimental research on the skiving cutting mechanism started relatively late. [PERSON] et al. [11] researched the variation patterns of tool cutting thickness during skiving, established a skiving cutting force calculation model, and verified the accuracy of cutting force calculations using finite element methods. [PERSON] et al. [12; 13] calculated and analyzed the working rake and clearance angles of cylindrical finishing skiving tools. [PERSON] et al. [14] conducted theoretical research on the cutting forces in skiving. [PERSON] et al. [15; 16] studied the minimum cutting thickness in skiving and developed an optimization calculation method for radial infeed based on this. Current cutting mechanism research of gear skiving is focused on the analysis of the changes in tool working angles, clearance angles, cutting forces, and chip shapes through kinematic or numerical simulations. However, the analysis of the cutting state and chip formation process during skiving is relatively poor.  
This paper first conducts kinematic simulations of gear skiving to study the variation patterns of cutting thickness and the distribution of cutting loads on the tool edges.  
Then, using numerical simulation calculations of gear skiving to analyze the changes in working angle, clearance angle, tool inclination, and cutting speed during the skiving process, it reveals the rule of cutting state and chip flow laws.  
Finally, based on the SPH finite element analysis method, the chip formation mechanism and the stress variation on the tool edges are studied. These analyses and calculations provide practical guidance for improving the service life of skiving tools.