Tribological and mechanical performance of sisal-filled waste carbon and glass fibre hybrid composites

This study has been carried out to show the use of natural fibres as the potential substitute of synthetic fibres in tribo-composites. The abrasive wear behaviour and mechanical properties of waste sisal/glass, sisal/carbon hybrid fibre reinforced polypropylene (PP) composites were analysed in this study. Results showed that increasing the sisal fibre weight content in the composites increases the coefficient of friction. The abrasion volume of sisal/glass hybrid composites showed significantly lower than those of sisal/carbon hybrid composite for the same hybrid ratios. This means that addition of sisal fibres on waste carbon and glass fibre reinforced PP composites decreased the potential of tribological performance. Although adding of sisal fibres as a natural substitute fibre source to waste short carbon fibre composites lead to inferior properties, an addition of sisal fibres to waste glass composites shows lower densities, comparable mechanical and abrasion volumes than that of waste glass fibre composites. This shows that sisal fibres can be used in place of glass fibres. The scanning electron micrographs of the fracture surfaces show that the wetting interaction of sisal and glass fibre with PP matrix is better than those of the sisal carbon hybrid composites. Furthermore, the worn surfaces of the sisal and its hybrid composites show vertical cracks, loose fragments, micro ploughing and transfer layers.