Influence of SiC nanoparticles addition on the microstructure and mechanical properties of stir-casted Zn-Al alloy

Abstract

ABSTRACT This study focuses on the synthesis of a Zn-Al alloy nanocomposite, incorporating varying weight percentages (2, 4, 6, and 8 wt.%) of SiC nanoparticles with an average size of 30 nm. The preparation was carried out using the stir casting technique. Experimental tests, including hardness, compression, and tensile tests, were conducted on both the Zn-Al alloy and its composite. Furthermore, the surface morphology of the materials was examined using scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The mechanical properties and microstructure of the composite samples were assessed. The results indicate that an increase in the weight percentage of SiC nanoparticles led to corresponding increases in hardness, compression strength, and ultimate tensile strength of the composite materials. When compared to an unreinforced alloy, nanocomposites reinforced with 2, 4, 6, and 8 wt.% SiC nanoparticles exhibited hardness improvements of 9.1%, 15%, 20.8%, and 30% respectively, as well as increases in ultimate tensile strength of 2.56%, 4.46%, 7.74%, and 12.21%, and compression strength enhancements of 17.5%, 20%, 22.4%, and 31.5% respectively. Notably, the composite sample containing 8% weight of reinforcement consistently demonstrated the highest ratings in terms of hardness, tensile strength, and compression strength. Based on the scanning electron microscopy (SEM) results, the nanocomposite alloy exhibits a dendritic morphology, with evenly distributed silicon carbide (SiC) particles embedded within the metal matrix. Furthermore, the interface between the SiC particles and the metal matrix demonstrates a strong bond. As a consequence, the mechanical properties of the fabricated composites were significantly improved.