Finite element modeling of indexable insert drilling processes in stainless steel

Indexable insert drills play a crucial role in high-performance drilling, particularly for large-diameter holes and difficult-to-machine materials. Although FEM is a powerful tool for analyzing and optimizing drilling processes, limited research has focused on indexable insert drills, and the efficient simulation of large-diameter drills with complex cutting geometries remains a significant challenge. This study presents an optimized and computationally efficient FEM model for indexable insert drills, developed in AdvantEdge™ 3D, capable of predicting thermomechanical loads (thrust force, torque, stress, temperature) and chip morphology during drilling and redrilling of AISI 316 L stainless steel. The key innovation lies in a computational approach that significantly reduces simulation time while maintaining high predictive accuracy. The model incorporates a novel tool–workpiece configuration with a slotted workpiece that enables the drill to reach nominal feed rate immediately upon engagement, accelerating convergence toward thermomechanical steady-state. Model optimization was achieved through a systematic evaluation of the most influential input parameters, surpassing the capabilities of previous FEM approaches and providing new validated insight into drilling process modeling. A comprehensive sensitivity analysis of Johnson–Cook flow stress parameters, friction coefficients, and mesh size was performed to optimize both accuracy and computational efficiency. The model was experimentally validated through complete-drill tests (both inserts mounted) and novel single-insert tests (one insert mounted) across a wide range of cutting conditions, including redrilling with varying pilot hole diameters. The optimized model accurately predicts torque, thrust forces, and chip morphology (average error: 16 %), while providing detailed stress and temperature distributions. Thrust force underprediction remains the primary limitation, identified as originating from the central insert, where Build-Up Edge (BUE) formation was observed at low cutting speeds near the drill tip. • Optimized FEM model predicts cutting loads and chip morphology in indexable drills. • Novel tool–workpiece setup reduces simulation time and ensures accuracy. • Johnson-Cook parameters and mesh size tuned for accuracy vs. computation trade-off. • Complete-drill and new single-insert tests validate FEM for drilling AISI 316 L. • Key contributing factors in drilling FEM accuracy were compressively analyzed.