Research on the influencing factors of chip forming in 304 stainless steel deep hole gun drilling

In the deep hole gun drilling process, the holes’ small diameter and long depth, combined with the narrow chip removal space, have made the relationship between process parameters and chip formation a persistent challenge in deep hole machining research. 304 stainless steel, known for its excellent wear and corrosion resistance, is widely used to manufacture deep-hole components. However, it also has processing difficulties, such as high hardness and poor plasticity. Therefore, this study focuses on 304 stainless steel, utilizing ABAQUS simulation software to model the chip formation process during deep hole gun drilling and investigate the effects of process parameters on chip formation. Based on the simulation results and employing fluid–structure interaction theory, a fluid–solid coupling simulation model was established using ANSYS Fluent software to study the impact of coolant pressure on chip formation. The relationship between coolant pressure and chip curling deformation at different stages of chip growth was elucidated. Subsequently, deep-hole gun drilling tests were conducted to analyze chip morphology. Scanning electron microscopy (SEM) was used to study the fracture mechanism of chips during the deep hole gun drilling of 304 stainless steel, ultimately revealing the relationship between chip formation and process parameters in this machining process.