Experimental investigation on the mechanical properties and water absorption behavior of randomly oriented short pineapple/coir fiber-reinforced hybrid epoxy composites

Abstract

To elevate the progressive utilization of natural fiber reinforced composites in structural applications, it is extremely required to heighten the properties of NFRC’s by the exploitation of hybridization tool. In most of the cases, the mechanical properties of hybrid composites reinforced with natural fibers are far better than the pure single fiber reinforced composites and comparable to the synthetic fiber reinforced composites. Therefore in this research work, an experimental investigation has been carried out to study the mechanical properties and water absorption behavior of hybridized PALF/COIR fiber reinforced epoxy matrix composites. The biocomposite sheets consist of randomly oriented and intimately mixed short fibers (20 mm in length) were fabricated by employing the hand lay-up technique at 11 levels of COIR fiber loading (0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 vol%) with fixed total fiber content (40 vol%). The mechanical properties (tensile strength, tensile modulus, flexural strength, flexural modulus, and impact strength) and water uptake behavior with water diffusion mechanism of various formulated composites have been studied according to ASTM standard. The total of four samples for each composite specimen was tested and their average values were reported. The results showed the improvement in tensile and flexural properties (strength and modulus) of COIR/Epoxy composite by the hybridization with pineapple leaf fiber, up to 50 vol%. The hybrid composite reinforced with equal volume content of pineapple leaf fiber (PALF) and coconut husk fiber (COIR) possess the highest tensile, flexural, and impact strength. Water absorption test revealed the decrement in sorption affinity with the increase of coir fiber content. The hybrid composite (P50-C50) absorbs 62% and 32% less water than that of pure PALF/Epoxy and COIR/Epoxy composites.