Microstructures and mechanical properties of Cu/Ti_3SiC_2/C/graphene nanocomposites prepared by vacuum hot-pressing sintering and hot isostatic pressing

摘要

Copper-graphite composite is an ideal friction material due to its good heat resistance, wear resistance and friction coefficient stability. The addition of Ti3SiC2 can improve strength, hardness and wear resistance of copper-graphite alloy material without affecting its self-lubricating properties and electrical conductivity. Two dimensional graphene has become an attractive composite reinforcement owing to their unique electrical, mechanical and thermal properties. Cu/Ti3SiC2/C/Graphene naocomposite materials reinforced with graphene have been fabricated by vacuum hot-pressing sintering and hot isostatic pressing. Microstructures and mechanical properties of Cu/Ti3SiC2/C/Graphene naocomposite materials with different graphene contents have been systematically investigated. Microstructures of the composites were examined by optical microscopy, X-ray diffraction, back scattered electron imaging, scanning electron microscope with energy dispersive spectrometer and transmission electron microscope. The mechanical properties were determined from Brinell hardness, tensile, compressive and shear tests. Results demonstrated that there was an optimum value of graphene content which has an impact on microstructures and mechanical properties of Cu/Ti3SiC2/C/Graphene naocomposite materials. Based on graphene content on microstructure and mechanical properties of Cu/Ti3SiC2/C/Graphene naocomposite materials, strengthening and fracture mechanisms by graphene reinforcement have been analyzed.