Influence of cutting tool geometry when milling Nomex honeycomb structure

The use of Nomex honeycomb structures is essential for the aerospace and aeronautics industry because of their high out-of-plane strength and their advantageous weight/rigidity ratio. Nevertheless, milling these structures presents technical and scientific challenges, including premature wear of cutting tools and the quality of the machined surface. In general, the machining process relies on carrying out experimental tests. However, the high rotation speed of the cutting tool makes it difficult to monitor the cutting process correctly. Thus, it has become imperative to adopt reliable numerical models to collect instantaneous and accurate physical data. For this purpose, a 3D finite element numerical model was developed using the Abaqus/Explicit software, taking into account the real conditions of the experiment. An experimental validation was carried out by analyzing the premature wear of the cutting tool. After having validated the numerical model, an in-depth analysis was carried out to evaluate the influence of the number of teeth of the cutting tool on the optimization of the machining of the Nomex honeycomb structure. This analysis specifically focused on the cutting forces, the quality of the machined surface, and the accumulation of chips in front of the cutting tool. The obtained results clearly underline that low feed rates improve the integrity of the cutting tool, while a limited number of cutting tool teeth significantly improves cutting forces and the quality of the machined surface.