Wear and mechanical properties of Al6061/SiC/B 4C hybrid composites produced with powder metallurgy

摘要

This study investigates the production of various reinforced and non-reinforced composite materials using powder metallurgy (PM). It presents the new approach into optimize the mechanical properties of hybrid composites (Al-SiC-B4C) produced with powder extrusion process. A16061 powders are used as the matrix material and B4C and SiC powders are used as the reinforcement materials. Matrix and reinforcement materials are mixed in a three-dimensional mixer. The mixtures are then subjected to cold pressing to form metal block samples. Block samples are subjected to hot extrusion in an extrusion mold after being subjected to a sintering process. This produces samples with a cross-sectional area of 25×30 mm2. These extruded samples were subjected to T6 heat treatment. The composite materials produced are examined in terms of density, hardness, transverse rupture strength, tensile strength, and wear resistance. Furthermore, optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy and XRD are performed to examine the microstructure, surface fractures, and surface abrasion. In this study, high density Al6061/B4C/SiC hybrid composite materials were successfully produced. After extrusion, some micro particles were found to crack. The highest hardness occurred in 12%B4C reinforced composites. The lowest hardness was obtained in Al6061 alloy without reinforcement. The highest tensile strength occurred in 12%SiC particle reinforced composite material. The highest wear resistance was obtained for 9%B4C+3%SiC samples due to the hardness of B4C and the good adhesion properties of the matrix and SiC.