Investigation on Mechanical Properties and Microstructure of B4C/Graphene Binary Particles Reinforced Aluminum Hybrid Composites

In the present study, boron carbide and graphene-reinforced aluminum hybrid composites with various boron carbide (1, 3, 6, 9, 12, 15, 30 wt%) and graphene nanoplatelets (GNPs) content (0.15, 0.30, 0.45 wt%) were produced by the powder metallurgy method. The method consists of mixing, ultrasonic dispersing, mixing, filtering, drying, pressing, and sintering processes. The apparent density, compressive strength, and Vickers hardness of the fabricated composites were determined by density meter, universal test machine, and micro Vickers hardness measurement device, respectively. The phase and microstructural analysis of the fabricated composites were analyzed using an X-ray diffraction device and scanning electron microscope, respectively. The maximum apparent density (2.54 +/- 0.005 g/cm(3)), the highest Vickers hardness (109.8 +/- 1.5 HV), the best compressive strength (244 +/- 5 MPa), and minimum porosity (4.0%) were obtained at Al-30%B4C-0.15%GNPs composite. The enhancement in Vickers hardness and compressive strength of Al-30%B4C-0.15%GNPs composite was detected as + 293% and + 190% compared with pure aluminum. In conclusion, it was detected that the mechanical strength of Al-30B(4)C-GNPs composites improved up to 0.15 wt%GNPs content. After 0.15 wt%graphene content, the mechanical strength of Al-30B(4)C-GNPs composites decreased due to the agglomerated graphene nanoparticles.