Reinforcement of Aluminium Matrix Composites with Particulate Agricultural Waste Derivatives for Automotive Applications: A Review

Abstract

The automotive industry faces a significant challenge in meeting the increasing demand for lightweight and eco-friendly vehicles with reduced energy consumption and lower air pollution. This challenge is driven by factors such as consumer preferences, strict government regulations, technological complexities, cost considerations and market acceptance. Aluminium metal matrix composites (AMMCs) are novel materials with high suitability to address this challenge. Currently, AMMCs used in the automotive industry are reinforced with conventional synthetic ceramic particulates and they have shown tremendous improvements over unreinforced alloys. These composites have wear resistance and strengths equivalent to that of cast iron but with about 67% less density. However, synthetic reinforcements are expensive, have limited availability, possess high abrasiveness, cause unwanted reactions, pose recycling difficulties and their production leads to the emission of greenhouse gases. It is now pertinent to consider the use of agricultural waste derivatives as possible substitutes for these conventional reinforcements. In this work, the various agricultural waste derivatives that have been used to reinforce Al matrixes were reviewed and the potentials of the resulting composites as promising candidates for lightweight automotive applications were assessed. It was concluded that agricultural waste derivatives contained hard ceramics particles which improved the mechanical, tribological, thermal and corrosion properties of AMMCs, making agro-waste derivatives reinforced aluminium metal matrix composites promising for the production of novel lightweight automotive components.