Microstructure and Microhardness of Mg/SiC Metal Matrix Composites Developed by Microwave Sintering

Magnesium is one of the lightest metals that are extensively used in automobile, aerospace, and medical industries. Pure magnesium is not suitable for physical applications due to low corrosion resistance. Therefore, various metals and ceramics are added to magnesium to improve its mechanical and physical properties. Consequently, the additives play significant role in the performance of the components. Nowadays, magnesium alloys and its composites are widely used in daily practices owing to their improved properties. In this article, Mg alloy/SiC metal matrix composites were developed through the microwave sintering. The AZ91 alloy was used as the metallic matrix and SiC as the reinforcement with a weight percentage of 5, 10, and 15. Scanning electron microscopy and X-ray diffractometry were used for phase and microstructural studies. Microhardness, density, and porosity were measured. Results revealed that density and microhardness increased with increasing percentage of reinforcement; consequently, the porosity decreased with the addition of SiC percentage. Results from SEM and XRD analysis have also confirmed the formation of phases that can improve the microhardness. © 2020, The Institution of Engineers (India).