Simulated Study of the Machinability of the Nomex Honeycomb Structure

Abstract

The Nomex honeycomb core has been widely used in many industrial fields, especially the aircraft and aerospace industries, due to its high strength and stiffness to heaviness ratio. Machining of the Nomex honeycomb structure is usually associated with tearing of the walls, deformations of the cells and the appearance of burrs. Therefore, milling of the Nomex honeycomb structure represents an industrial hurdle challenge for scientists and researchers about the quality of the machined surface and the integrity of the cutting tool. In response to this problem, we have developed a three-dimensional numerical model of finite elements based on the real conditions of experimental work by means of the analysis software Abaqus. Based on the developed numerical model, an experimental validation was performed by comparing the quality of the surface and the adhesive wear of the cutting tool determined from the numerical simulation and that established by the experiment. In addition, the effect of geometric parameters in terms of wedge angle and cutting tool diameter on material accumulation, chip size, generated surface and cutting forces was analyzed. The results of the quantitative analysis prove that the choice of cutting conditions and cutting tool geometry in terms of favorable rake angle and tool diameter improves the surface quality of the generated part and optimizes the integrity of the cutting tool.

Numerical Simulation of Rotary Ultrasonic Machining of the Nomex Honeycomb Composite Structure

“…In this analysis, the damage method used aims to decrease the stiffness of the individual elastic modules as soon as the breaking point is reached. For the Tsai-Wu criterion, the damage assessment is carried out based on several variables denoted as dk (with k ranging from 1 to 6), as illustrated by Equations ( 9) and (10). The formula describing the reduction in stiffness depends on the type of material and its mechanical behavior.…”

“…However, despite the optimization of specially designed machining tools, the conventional machining process has significant shortcomings in terms of machining accuracy and the quality of the machined surface. In the fact, the problems with the machined surface of the NHC core manifest themselves in the form of burrs, cell deformation and the tearing of aramid fibers [10]. Consequently, conventional machining fails to deal effectively with these peculiarities, resulting in a poor machined surface.…”

Three-Dimensional Finite Element Modeling of Ultrasonic Vibration-Assisted Milling of the Nomex Honeycomb Structure

“…Due to their notable mechanical properties, Nomex honeycomb structures are widely used in these sectors, particularly in the manufacturing of aircraft wings and tails [5,6]. However, shaping these structures presents a challenge due to the geometry of the NHC core and the fragility of the Nomex paper that comprises it [7]. Shaping of the honeycomb structure is usually carried out through conventional processes such as cutting using thin-bladed tools [8].…”

Enhancing the Machining Performance of Nomex Honeycomb Composites Using Rotary Ultrasonic Machining: A Finite Element Analysis Approach

“…Regarding their physicochemical properties, NHCs exhibit satisfactory characteristics in terms of corrosion resistance, fire resistance and dielectric properties, thus improving their performance under extreme requirements [5,6]. Machining the Nomex honeycomb core represents a critical step in the manufacturing of composite structures, as it directly influences the final quality and performance of the structure [7]. However, this operation represents a major challenge due to the specific characteristics of the Nomex material, considered fragile, and the complex geometry of the honeycomb structure.…”