Amélioration de la résistance d’impact d’un bord d’attaque d’un avion en alliage d’aluminium par des matériaux composites

Abstract

Impact resistance is at the forefront of the challenges in aeronautics. The appearance of composite materials offers new avenues for reflection to improve the resistance of structures to impact. The main objective of this research is to study the mechanical behaviour of the leading edge of a 2024T351 aluminium alloy aircraft wing with a view to improving it. More specifically, the aim is to use criteria such as variations in the internal energy, kinetic energy and velocity of the projectile following impact to propose a more resistant coating solution. To do this, three case studies are carried out. The first proposes to compare the impact performance of aluminium with unidirectional composite materials, namely carbon-epoxy, glass-epoxy and kevlar-epoxy. In this study, the leading edge reference material, aluminum, is replaced successively by these three materials. A detailed analysis of the ballistic impact performance is conducted on each of the three at four different stacking sequences. It turns out that carbon-epoxy has a relatively higher internal energy absorption capacity than the other materials. It also shows a better performance in terms of the internal energy of the leading edge and the velocity lost by the projectile. However, the performance of this solution remains inferior to that of the aluminium alloy. In light of these results, a second case study is proposed. It consists of changing the geometry of the composite leading edge while maintaining the same weight as aluminum. Despite this modification, the 2024T351 aluminum remains better performing at impact than the three composite materials studied. The ABAQUS software is used for simulation and calculation purposes. The behaviour of unidirectional composite materials is modelled using a user-defined material subprogram (VUMAT). The Hashin criterion is adopted for fiber failure. The matrix failure modes meet the Puck criterion.

Date	19 Aug 2020
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Anh Dung Ngô (Supervisor)