Effect of snail shell powder addition on mechanical and microstructure behaviour of mercerized roselle fiber reinforced epoxy resin-based hybrid composite

Abstract

Hybrid composites are materials composed of a combination of two or more different types of reinforcements, often with distinct properties. The combination of different reinforcements aims to exploit the strengths of each material, resulting in a composite with improved mechanical, thermal, or other specific properties compared to individual components. Nowadays, application of hybrid composites reinforced with natural fibers has gained significance in various industries due to the unique combination of properties such as automobile, aerospace, construction, Sports and Leisure. Eventhough, natural fibers may degrade over time due to environmental factors, resulted in decrease in mechanical properties and overall durability of the hybrid composite. Therefore, Hybrid composites can achieve a combination of high strength, stiffness and toughness that is difficult to obtain with single-fiber composites. The aim of the study is to develop roselle fibers reinforced epoxy resin-based hybrid composite using hand layup method. The snail shell powder with different weight proportion (5, 10 & 15 wt.-%) and 20% (wt.-%) of roselle fiber have been added to fabricate the hybrid composite. The study was carried out in order to study the mechanical properties such as tensile, flexural, impact and hardness strength. The results showed that the composites fabricated with 10% of snail shells powder showed the maximum tensile strength of 40 MPa, flexural strength of 57 MPa and impact strength of 31 KJ/m2. The 15% filler added composite showed the maximum hardness strength of 43 HV. It was observed that the fracture mechanism of a hybrid composite involves fiber breakage, matrix cracking, delamination, matrix debonding, crack initiation and voids etc were formed in the composite. The Composite samples embedded with fillers demonstrate the lowest water intake behaviour. The findings showed that the hybrid composite with 10% snail shell powder exhibited the highest tensile, flexural and impact strength while the 15% snail shell powder composite showed the highest hardness (43 HV). Additionally, snail shell embedded composites demonstrated the lowest water intake behaviour. Fracture analysis revealed mechanisms such as fiber breakage and matrix cracking observed via SEM.