Synergistic effect of graphene/boron nitride binary nanoparticles on aluminum hybrid composite properties

Abstract

In this study, hexagonal boron nitride nanoparticulates (BN: 0.5, 1, 1.5, 2 wt.%) and graphene nanoplatelets (GNPs: 0.15, 0.30, 0.45 wt.%) reinforced hybrid aluminum matrix composites were produced via the powder metallurgy (PM) process. In this process, mixing, dispersing, drying, filtering, compaction, and heat treatment were applied. The microstructure, Vickers hardness, density, compressive strength, and phase analysis of Al-BN, Al-BN-graphene composites, and pure Al were evaluated. The phase and microstructural analyses of the specimens were examined by an X-ray diffraction device and a scanning electron microscope. The results showed that maximum density (2.63 ± 0.01 g/cm3), minimum porosity (2.6%), maximum micro Vickers hardness (58 ± 1.5 HV), and the highest ultimate compressive strength (260 MPa) were achieved at Al-1BN-0.15GNP composite compared with pure Al and Al-BN. A significant improvement in ultimate compressive strength and micro-Vickers hardness of Al-1BN-0.15GNPs was obtained as ~ 225% and ~ 87% in comparison with those of pure aluminum. As a result, the mechanical properties of Al-BN-GNP hybrid composites were improved up to 1%BN and 0.15%graphene contents. Over these contents, the mechanical strength deteriorated due to the clumping of GNPs and nano-BN particles.