Effect of SPS Process on Tensile Properties of Graphene Nanosheet Reinforced Aluminum Matrix Composites

Graphene nanosheet reinforced aluminum composites (GNFs/Al) containing 0.5wt% GNFs were fabricated by spark plasma sintering (SPS) with different temperatures and holding time. The microstructure and tensile properties of the composites were investigated. The results show that the composites sintered at lower temperatures (500 degrees C) possess weaker interfacial bonding, which results in lower tensile properties. When sintered at higher (560 and 590 degrees C) temperatures, the interfacial bonding of the composites is obviously enhanced. To avoid interfacial reactions at higher temperatures, rapid sintering is essential. Therefore, the composites sintered at 560 degrees C/4 min exhibit a tensile strength of 142 MPa, which is 31% higher than that of pure Al. The enhanced tensile properties of the GNFs/Al composites in this study can be ascribed to the refinement and stress transfer of the aluminum matrix grains.