Analysis of natural fibre composites for aerospace structures

Abstract

Purpose The main idea is the comparison between composites including natural fibres (such as the linoleum fibres) and typical composites including carbon fibres or glass fibres. The comparison is proposed for different structures (plates, cylinders, cylindrical and spherical shells), lamination sequences (cross-ply laminates and sandwiches with composite skins) and thickness ratios. The purpose of this paper is to understand if linoleum fibres could be useful for some specific aerospace applications. Design/methodology/approach A general exact three-dimensional shell model is used for the static analysis of the proposed structures to obtain displacements and stresses through the thickness. The shell model is based on a layer-wise approach and the differential equations of equilibrium are solved by means of the exponential matrix method. Findings In qualitative terms, composites including linoleum fibres have a mechanical behaviour similar to composites including glass or carbon fibres. In terms of stress and displacement values, composites including linoleum fibres can be used in aerospace applications with limited loads. They are comparable with composites including glass fibres. In general, they are not competitive with respect to composites including carbon fibres. Such conclusions have been verified for different structure geometries, lamination sequences and thickness ratios. Originality/value The proposed general exact 3D shell model allows the analysis of different geometries (plates and shells), materials and laminations in a unified manner using the differential equilibrium equations written in general orthogonal curvilinear coordinates. These equations written for spherical shells degenerate in those for cylinders, cylindrical shell panels and plates by means of opportune considerations about the radii of curvature. The proposed shell model allows an exhaustive comparison between different laminated and sandwich composite structures considering the typical zigzag form of displacements and the correct imposition of compatibility conditions for displacements and equilibrium conditions for transverse stresses.

Review of natural fiber-reinforced engineering plastic composites, their applications in the transportation sector and processing techniques

“…In terms of source, natural fibers are classified into animal fibers, plant fibers, and minerals fibers. 10,16,17,[19][20][21][22][67][68][69][70] Plant fibers in turn classified into six types: bast fibers, leaf fibers, seed/fruit fibers, straw/stalk fiber, grass fiber, and wood fiber. 10,71,72 Classification of natural fiber is presented graphically in Figure 2.…”

“…25,109 The wide range of applications is because of natural fiber's low specific weight, abundancy, low cost, good mechanical properties, biodegradability, renewability, low energy consumption in production, and good corrosion and fatigue resistance compared to synthetic fibers such as glass, carbon, and aramid, which are less biodegradable and derived from nonrenewable sources. 3,19,25,[109][110][111] A brief comparison of natural fibers with glass and carbon fibers is shown in Table 7. Natural fibers have higher specific strength than glass fiber and equivalent specific modulus.…”

“…6 Additional benefits of composites made up of natural fibers over synthetic fibers include low cost, renewability, recyclability, biodegradability, carbon neutrality, nonabrasive quality, limited health risks, acoustic, heat and electrical insulation qualities, and ease of dispose. 5,6,11,13,[17][18][19] On the other hand, natural fibers composites have a number of drawbacks, such as high moisture content, low fire resistance, weak interfacial adhesion, poor resistance to microbial attack, and a need to use low processing temperatures. 14,20,21 Many of these problems can, however, be resolved with appropriate surface treatment techniques.…”

Structural optimization of a composite launch tube of man portable air defense system

“…Composite materials are used in many different sectors such as aviation, automotive, sports and biomedical. The reason why composite materials are preferred is that they show high mechanical and physical strength properties at low weights compared to many conventional materials (Elmarakbi, 2013; Brischetto, 2018; Sharma et al , 2019). The use of composite materials is continuously increasing.…”

Experimental investigation on the mechanical properties of aluminium sandwiched sisal/kenaf/aloevera/jute/flax natural fibre-reinforced epoxy LY556/GY250 composites

“…In terms of stress and displacement values, composites including linoleum fibres can be used in aerospace applications with limited loads. 11 The fibres in kenaf are found in the bast and core. The bast constitutes 40% of the plant.…”