Enhanced tensile properties of magnesium composites reinforced with graphene nanoplatelets

The aim of this studys is to fabricate magnesium reinforced metal matrix composites using graphene nanoplatelets (GNPs) via powder metallurgy processing in order to enhance room temperature mechanical properties. The microstructural evaluation and mechanical behaviors of composite powders and extruded bulk materials were examined by X-ray diffraction (XRD), differential scanning calorimetry (DSC), Raman spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM) equipped with energy-dispersive spectrometer and mechanical tests. The uniform dispersion and large specific surface area per volume of GNPs embedded in magnesium matrix led to increament in microhardness, tensile strength and fracture strains of the composites. For example, when employing the pure magnesium reinforced with 0.30 wt% GNPs, the increase of Young׳s modulus, yield strength, and failure strain of extruded nanocomposite was +131%, +49.5% and +74.2% respectively, compared to those of extruded materials with no GNPs additive. Additionally, mechanical properties of synthesized composites were compared with previously reported Mg-CNTs composites. It was found that GNPs outperform CNTs due their high specific surface area.