Nanofillers’ Effects on Fracture Energy in Composite Aerospace Structures

Abstract

Composite materials damage behaviour is, nowadays, extensively investigated in the frame of aerospace research programmes. Among the several failure mechanisms which can affect composites, delamination can be considered as the most critical one, especially when combined to compressive loading conditions. In this context, nanofillers can represent an effective way to increase the composites fracture toughness with a consequent reduction of the delamination onset and evolution. Hence, in this paper, the toughening effect of the nanofillers on the delamination growth in composite material panels, subject to compressive load, has been numerically studied. A validated robust numerical procedure for the prediction of the delamination growth in composite materials panel, named SMXB and based on the VCCT-Fail release approach, has been used to perform numerical analyses by considering two different types of nanofillers. Reference material, without nanofillers insertion, has been used as benchmark in order to assess the capability of nanofillers to enhance the fracture toughness in composite laminates.

An Experimental Assessment on the Influence of Carbon Nanotubes Matrix Charging on the Fatigue Behavior of Composite Laminates

“…The reason for the increasing usage of these fillers is the improvement observed in composites fracture behavior, particularly in terms of fracture toughness. [ 1 ] There are many factors influencing the properties of nanocomposites, such as the density of the fillers within the matrix and, more in general, the manufacturing processes, which may lead to poor laminates quality affecting the mechanical properties of such innovative materials. Therefore, the assessment of the damage behavior of polymer composites reinforced with nanoparticles or nanotubes, which are expected to have superior mechanical properties, is still a challenge.…”