Processing of Graphene/CNT-Metal Powder

Abstract

In recent days, the demand for powder metallurgy components has increased due to unusual combination of properties. Carbon allotropes such as graphene and CNT are the novel material to enhance the properties of powder metallurgy component. However, processing of such materials is in infancy stage due lack of advance processing technique. This can be addressed through integration of several fabrication techniques to meet the industrial demands. The processing method and its important parameter will define the final property of the component. Such materials have found its applications in various fields like, sports, bio implants, aerospace and automobile sector.materials. Today, the most man made engineered composites includes mortar; concrete; reinforced plastics; ceramic composites and metal composites. Particulates, whiskers/short fibers are the common type of reinforcements (Figure 1) used successfully for the fabrication of composite. Particulates are available in platelets, spherical and various regular or irregular shapes which may be having equal geometry in all directions. The particulate reinforcement was limited to 30-40 vol% in the composite due to its brittleness and fabrication difficulties. Fiber glasses were the first modern composites and are used for sports materials, car bodies, ship and other structural applications. But, due to the advancement in the composite technology, carbon fibers replaced the glass reinforcement in the composite and were used for many expensive sporting equipment and aircrafts structures. Carbon nanotube is being used successfully in these days for making of stronger and lighter composites. Another advantage of any composite material is that their properties are tailorable to certain extent along any direction. Further, these developed composite materials have design-flexibility, close tolerance, high durable, chemical inert and corrosive resistance. Also, the innovation in the fabrication techniques and combination of advanced materials resulted in superior thermal stability, high temperature retention and outstanding electrical properties. Composite materials are used for various applications such as building blocks, structures, bridges, automobile components, race car bodies, aerospace structural materials, space crafts and more. Metal matrix composites (MMCs)Metal matrix composites (MMCs) comprises lightweight and low-density materials (aluminum, magnesium, copper, etc.) reinforced with fiber or particulate of ceramic (silicon carbide, alumina, graphite, etc.). MMCs gave the opportunity to tailor the desire properties for specific applications. The important properties of metal matrix composites are stiffness, specific strength at elevated operating temperature and high tribological performance. On the other hand, fabrication cost of MMCs found to be higher for high performance application such as space and military and conceding the ductility and toughness. Also, MMCs have wide applications and are used in jet engines, aircrafts, satellite materials, and piston mater...

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