Experimental investigation of layering pattern arrangements on mechanical, swilling and water absorption behavior of flax/coir fiber based bio-epoxy composites

Abstract

As natural fibres are recyclable and biodegradable, they are essential to the creation of ecologically sound composite materials. When compared to synthetic fibres, they have benefits including less environmental impact, superior mechanical qualities, and a lightweight nature. Gaining knowledge about and improving the usage of natural fibres in composites can result in environmentally friendly solutions that have a lower carbon footprint and more durability across a range of uses. The present research concentrates on the manufacture of hybridized bio-composites with eco-friendly epoxy as the matrix phase and flax as well as coir fibre mats as reinforcing agents. The hybridized composites of flax (F) and coir (C) fibres were created using a low-cost manual lay-up approach, accompanied by a hot press containing various stacking sequences. The materials' static characteristics, like inter-laminar shear strengths (ILSS) as well as hardness, were investigated. Physical parameters like water absorption and swelling thickness were also investigated. The experimental findings demonstrate that whenever the layering pattern was changed, bio-composites displayed small variations in strength properties. The FFFF sample had the greatest ILSS result of 7.69 MPa. Short beam breakdowns feature such as perpendicular inter-laminar shear fractures, micro buckling, and fibre breakage have also been observed. Although there were some advantages in the mechanical properties of bio-composites over eco-friendly epoxy, there were no significant consequences for modifying the toughness characteristics of a fibre sheet's cross-ply. This might be attributed to the low interaction of coir and flax strands, in addition to the hybrid composite specimens' poor interfacial bonding and strength. In comparison to their hybrid equivalents, pure fibre or non-hybrid materials demonstrated greater resilience to water uptake as well as thickness swelling.