Mechanical and microstructural analysis of Al-Al_2O_3/B4C hybrid composites

摘要

The present work aims to enhance the mechanical performance of monolithic Al alloy and single reinforced metal matrix composite using a hybridization technique. The microparticles of alumina and boron carbide were reinforced into cast Al alloy (6061) in a systematic varying ratio (i.e.100/0, 75/25, 50/50, 25/75 and 0/100) to prepare the hybrid metal matrix composites via stir casting method. The mechanical properties (i.e. tensile, impact, hardness and flexural) of the prepared composites were investigated as per ASTM standards. Furthermore, microstructural analysis of unfractured and fractured composite samples was also carried out using Scanning Electron Microscope. It was observed that hybrid composites comprising of microparticles revealed an enhanced tensile, flexural and hardness properties, and reduced impact energy and porosity as compared to Al alloy and single reinforced metal matrix composites. The highest values of tensile strength and modulus were offered by a hybrid composite (B50A50), which was 40% and 52.12% higher than that of Al alloy. Furthermore, there was an improvement of 105.72% in flexural strength and a reduction of 23.88% in impact energy for composite B50A50 than that of Al alloy. The present developed hybrid metal matrix composites can be proposed to be used in automobile parts and construction applications.