Dominating influence of cutting-edge lead angles on arc-trajectory machining of Nomex® honeycomb composites by using a straight blade cutter

Abstract

Nomex® honeycomb composites (NHCs) with circular arc features are a challenging issue in the machining of aviation curved structural components. Compared to linear feature machining, arc feature machining involves six-axis coordinated motion, introducing additional variables. Directly referencing the linear feature machining process will lead to the deterioration of contour accuracy and surface quality in arc-trajectory machining (ATM). To further explore the influence of process variables on ATM, this study developed an error model for straight blade tool (SBT) ATM and investigated the influence of cutting-edge lead angles (γ) on contour accuracy and surface quality. A vertical cutting process was proposed, and experiments proved it provided the optimal machining quality (the defect rate of core cells was only 3.93 %) compared to forward and backward inclination cutting (7.23 %∼34.3 % and 9.71 %∼17.36 %, respectively). Additionally, it was revealed that the main reason for the deterioration of surface quality on ATM was the excessive angle between the cutting edge direction and the feed direction. Based on the results above, the influence and optimization of cutting-edge lead angles were revealed, and the advantage of vertical cutting process for machining NHCs with arc-trajectory was demonstrated. This research provides a feasible method for the machining of NHCs with arc-trajectory using SBT.