Analysis of the effect of tool wear and breakage in milling 508III steel on chip morphology

The water chamber head is a critical component of nuclear power equipment, manufactured from 508III steel. During the milling process, the tool is subjected to high mechanical impact and cutting temperatures, making it highly susceptible to severe wear and breakage. If tool failure is not identified and the tool is not replaced promptly, it will lead to cutting anomalies. Chip morphology is closely related to tool condition and therefore serves as an important basis for identifying tool condition. By analyzing the influence of tool condition on chip morphology, this can provide the theoretical basis and technical support for tool condition identification based on chip morphology. Firstly, a milling experiment was conducted on 508III steel to collect chip samples at different stages of wear and breakage, and the changing law of chip morphology was analyzed. Secondly, the cutting tool’s wear and breakage were observed, and the formation of chips and the causes of curling deformation were discussed. Furthermore, the changes in chip morphology after edge wear, groove wear, and fatigue breakage of the cutting tool are discussed. Edge wear affects the degree of upward curling of the chip, whereas groove wear and breakage primarily affect the degree of lateral curling of the chip. Finally, finite element simulations of chip morphology under no tool wear, edge wear, and groove wear are performed to confirm the changes in chip morphology.