Investigation on damage reduction method by varying cutting angles in the cutting process of rectangular Nomex honeycomb core

Abstract

Nomex honeycomb component is a typical weak rigid structure, leading to various damages during cutting operation. In this paper, the effects of cutting angles, entrance angle and engagement angle, on cutting quality were analyzed by focusing on the cell wall deformation, the cutter-workpiece interaction and the thin-walled cell geometry. A damage reduction method was proposed by controlling the range of the cutting angles. Experiments were conducted to verify the damage reduction method by cutting rectangular Nomex honeycomb core using multi-teeth disc cutters. The results showed that the method has a remarkable effect on the characteristics and distributions of damages by varying cutting angles: (a) the experimental damage-prone range of entrance angle is 55° ~ 75°, and an entrance angle near to 0° or 180° is more beneficial to damage reduction; (b) when engagement angle is smaller than 90°, there will be no visible tear damage; (c) up-cutting direction that makes entrance angle larger than 80° and engagement angle smaller than 90° is effective for damage reduction, leading the damage size is reduced by at least 40%; (d) engagement angle decreases as increasing cutting edge inclination so that the damage size can be further reduced by at least 70%.