A Novel Approach in Developing Aluminum Hybrid Green Metal Matrix Composite Material Using Waste Eggshells, Cow Dung Ash, Snail Shell Ash and Boron Carbide as Reinforcements

Abstract

Global development of aluminum metal matrix composite (AMC) in research, industries and defense with reduced weight, enhanced strength and low cost leads to the establishment of a new hybrid green metal matrix composite using aluminum (Al) alloy as base material with silicon carbide (SiC) and reinforcing it with waste carbonized eggshells (WCE), cow dung ash (CDA), snail shell ash (SSA) and boron carbide (B4C) by altering the different reinforcement weights using stir casting mechanism. Experimental results showed increased hardness, tensile strength and fatigue strength, while decrease in fracture toughness, ductility and corrosion rate which improved by heat treatment. The optimum values obtained were 7.5 wt% of WCE and SiC + SSA; preheat temperature of WCE and SiC was 300 °C and 500 °C, respectively. The stability and non-reactivity factors of the reinforcements were stringently considered at optimum temperature. Mono-ethylene glycol (MEG) in aqueous solution was used for experimenting different samples of AMC with varying proportion of SSA. The hardness of the Al alloy incremented to maximum when 7.5 wt% SiC + 7.5 wt% SSA was added and decremented when 10 wt% SiC + 10 wt% SSA was used as reinforcements. The results inferred that using WCE as reinforcement with the Al matrix gave better tribomechanical properties at a much cheaper rate than uncarbonized eggshells (ES) and SiC + SSA. The overall objective was to introduce a novel hybrid AMC by recycling and reutilizing wastes.