Cutting performance optimization and experimental research of indexable insert drill

In this study, the entire process of entry-drilling cutting and steady-state cutting of indexable insert drills was investigated to address challenges, such as vibration, chipping, and poor machining quality, during the cutting process. The research involved the utilization of theoretical analysis and simulation to examine the three-stage force of entry drilling and steady-state force of drilling bodies with various lap structures. Different parameters of the lap structure were analyzed to understand their impact on the direction of the cutting force, emphasizing that the force direction was influenced more by lap structure than the size of the cutting force. Data on radial force, axial force, hole diameter, hole wall roughness, and drill scraping were obtained from experimental cutting of carbon and stainless steel. The performance of different lap structures was evaluated based on these parameters. The experimental results revealed that the radial force in the given environment was most significantly impacted by the height difference between the central and peripheral insert. This was followed by the central insert deflection angle α₂ and peripheral insert deflection angle α₁. A larger deflection angle β resulted in a skewed radial force direction toward the outermost end of the peripheral insert, minimizing drill body scraping and increasing radial force. Furthermore, a substantial increase in radial force and axial force was observed with an increase in feed, while these forces were not significantly affected by the increase in cutting speed. Additionally, the hole diameter and hole wall roughness after cutting increased with the rise in feed.