Improvement of the mechanical and wear properties of Al6061 alloys with quartz and SiC hybrid reinforcements by powder metallurgy

Abstract This study aims to explore the potential of quartz, a naturally abundant mineral, as a reinforcing material in the fabrication of metal matrix composites. Al6061 alloy was selected as the matrix material due to its widespread application in the automotive industry. Silicon carbide (SiC), a commonly employed reinforcement in composite manufacturing, was incorporated as a secondary reinforcement in the production of hybrid composites, enabling an investigation into its compatibility with quartz. The composites were fabricated via the powder metallurgy (P/M) technique. Microstructural analysis demonstrated the integration of quartz within the internal structure, revealing a nearly homogeneous distribution of reinforcements with minimal agglomeration. Micro Vickers hardness testing revealed that introducing 10 % quartz enhanced the hardness of the Al6061 alloy by 79.69 %. The most pronounced hardness improvement, however, was achieved in the hybrid composite reinforced with 5 % SiC and 7 % quartz, exhibiting a 108.95 % increase. Wear resistance generally improved by up to 10 % as the reinforcement fraction increased. Notably, the composite reinforced with 5 % SiC and 7 % quartz exhibited the greatest enhancement in wear resistance, surpassing the unreinforced alloy by 369.23 %. Furthermore, the thermal conductivity (TC) coefficient of the composite reinforced with 7 % quartz decreased by 7.54 % relative to the unreinforced alloy.