Development of Flax Fibre based Textile Reinforcements for Composite Applications

Abstract

Most developments in the area of natural fibre reinforced composites have focused on random discontinuous fibre composite systems. The development of continuous fibre reinforced composites is, however, essential for manufacturing materials, which can be used in load-bearing/structural applications. The current work aims to develop high-performance natural fibre composite systems for structural applications using continuous textile reinforcements like UD-tapes or woven fabrics. One of the main problems in this case is the optimisation of the yarn to be used to manufacture the textile reinforcement. Low twisted yarns display a very low strength when tested dry in air and therefore they cannot be used in processes such as pultrusion or textile manufacturing routes. On the other hand, by increasing the level of twist, a degradation of the mechanical properties is observed in impregnated yarns (e.g., unidirectional composites) similar to off-axis composites. Therefore, an optimum twist should be used to balance processability and mechanical properties. Subsequently, different types of fabrics (i.e., biaxial plain weaves, unidirectional fabrics and non-crimp fabrics) were produced and evaluated as reinforcement in composites manufactured by well established manufacturing techniques such as hand lay-up, vacuum infusion, pultrusion and resin transfer moulding (RTM). Clearly, as expected, the developed materials cannot directly compete in terms of strength with glass fibre composites. However, they are clearly able to compete with these materials

Comparison of damage behaviour of different plant fibre composites under laser impact loading

“…Particularly, PIMM leads the project Hephaistos with PPRIME to install a new generation of laser shock generation for LASAT Technique. 6 Instytut Maszyn Przeplywowych of the Polish Academy of Sciences (IMP PAN, www.imp.gda.pl) has been established in Gdansk. The Department of Mechanics of Intelligent Structures, led by Prof. Ostachowicz, is particularly specialised in non-destructive damage detection methods.…”

“…They have a lower carbon footprint and their specific properties are comparable to the ones of glass fibers due to their low density [2][3][4]. They already constitute attractive substitutes to glass fibers as polymer reinforcement for some semi-structural applications [5][6][7]. High strain rate behaviour of those eco-composites is not well known yet.…”

Complex Shape Forming of Flax Based Woven Fabrics - Analysis of the Yarn Tensile Strain during the Process

“…It has also been chosen because fabric manufactured from highly twisted yarns exhibit low permeability preventing or partially preventing the use of processes from the LCM (Liquid Composite Moulding) family. Untwisted yarns have also been chosen because manufactured composites display better mechanical properties than composites made with twisted yarns [24].…”

Experimental Investigation of the Effect of Short Flax Fibers on the Permeability Behavior of a New Unidirectional Flax/Paper Composite

“…The manipulability of the loose yarns and the integrity of their orientation under forces induced by RTM resin flow can become problematic. To cope with this, further processing is used to maintain cohesion among UD yarns, typically by weaving or stitching [6,7]. Not only do these processes induce further costs, but they are also known to negatively impact mechanical properties: weaving induces local fiber curvatures while stitching locally destructs fiber integrity [6,7].…”

“…To cope with this, further processing is used to maintain cohesion among UD yarns, typically by weaving or stitching [6,7]. Not only do these processes induce further costs, but they are also known to negatively impact mechanical properties: weaving induces local fiber curvatures while stitching locally destructs fiber integrity [6,7]. After being chemically treated and combed, natural fibers must further be twisted in the form of yarns.…”