10th U6+ Consortium of African Universities International Conference

Interior panels manufactured from foams and synthetic fibres consume significant amounts of energy during production, are non-biodegradable, and are difficult to recycle. On the other hand, agricultural waste continues to accumulate as the population increases. Natural fibres and agricultural residues are increasingly being incorporated into engineering applications because their mechanical properties are comparable to those of synthetic fibres. However, natural fibres often exhibit inconsistent behaviour when used individually. Therefore, there is a need to develop bio-composites consisting of filler materials and natural fibres to improve mechanical performance and material sustainability. This study compares the influence of hemp fibre–macadamia filler and coconut fibre–macadamia filler composites on the mechanical properties of bio-composites. Macadamia shells were crushed using a mortar and pestle and then sieved to obtain particle sizes smaller than 14 mm. The coconut and hemp fibres were characterized using scanning electron microscopy (SEM) for morphological analysis, chemical treatment with 5% sodium hydroxide, and moisture absorption testing. Thereafter, the bio-composites were fabricated using the hand lay-up method. Mechanical tests, including tensile and flexural strength tests, were performed using universal testing equipment. Non-destructive testing, specifically Leeb hardness testing, was also conducted on the fabricated bio-composites. Finally, water absorption tests were carried out to evaluate the moisture uptake behavior of the composites.