Mechanical properties and corrosion behaviour of ZN-27AL based composites reinforced with silicon carbide and bamboo leaf ash

The mechanical and corrosion behaviour of Zn27Al alloy based metal matrix composites reinforced with silicon carbide and bamboo leaf ash (BLA) was investigated. Double stir casting method was used to produce the composites which contained 7 and 10wt% BLA-SiC particles consisting of 0, 20, 30 and 40% BLA, respectively. Microstructural examination, mechanical properties and corrosion behaviour were used to characterize the composites produced. The results show that the hardness and tensile strength of the composites decreased with increase in the weight percent of BLA although less than 11% for all experimental cases studied. The percent elongation (%E) improved slightly with the addition of a maximum of 30% BLA content for both the 7 and 10 wt% composite grades while the fracture toughness increased consistently with increase in the weight percent of BLA in both the 7 and 10 wt. % composite grades. The BLA-SiC containing Zn-27Al hybrid composites were very stable in 3.5% NaCl solution and the corrosion resistance in 0.3M H2SO4 solution was superior to that of the single SiC reinforced Zn-27Al composite grade.