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Characterization of metal-carbon nanotube composites14eueuJuly/August 2017 | MicroscopyandAnalysisINTRODUCTIONThe hunt for finding a material which can perform under adverse environmental conditions is never ending since the birth of mankind. This has encouraged researchers to take up challenges to find new materials having desired properties and applications. At present metal matrix composites (MMCs) have generated a wide interest because of their high strength, stiffness and fracture toughness1-3. Beside this they can also resist elevated temperatures in corrosive atmospheres. In MMCs the metal, the alloys used as matrices and the reinforcement need to be stable over a range of temperature whilst being non-reactive. The choice of the reinforcement depends on the matrix material and the application of the MMC. The strength-to-weight ratios of resulting composites can be higher than most of the metals and alloys4, 5. Several factors such as melting point, physical and mechanical properties of the composites at various temperatures determine the service temperature of the composites6, 7.Copper (Cu) shows high formability, high resistance to oxidation and corrosion and has a special place among all metals because of its high electrical (5.96×107 S/m) and thermal conductivity (401 W/mK). So, the most universal application of Cu is where high electrical and thermal conductivity are desired. There has been considerable interest in academia as well as industry in the use of Cu-based metal matrix composites in past few decades. Cu is an outstanding material for electrical applications whose competence can be enhanced by refining its mechanical properties8.Carbon nanotubes have emerged as promising reinforcement for a variety of nanocomposites because of their geometry, mechanical strength, chemical stability and electrical conductivity since their discovery in the early 1990s. Single walled carbon nanotubes (SWCNTs) consist of a single layer graphene sheet wrapped to form a tube structure having diameters at nanoscale.Several experiments and simulations reported that CNTs have surprising mechanical properties as illustrated by an elastic modulus of 0.3-1TPa, tensile strength of the order of 10-60 GPa and thermal conductivity of up to 3000 W/mK. Carbon nanotubes come in two principal forms, single walled carbon nanotubes (SWCNT) and multiwalled carbon nanotubes (MWCNT)9-12. The density of multiwalled carbon nanotubes (MWCNTs) is 2.60 g/cc and their specific surface area is about 200-400 m2/g. Cu-based metal matrix composites having carbon nanotubes as reinforcement are used for structural applications and functional materials because of their high strength and excellent electrical and thermal conductivity.It has been reported in literature that with the addition of carbon nanotubes the bulk properties of Cu can be improved. The Cu-based MMCs reinforced with CNTs have superior mechanical properties and are more thermally stable compared to pure Cu13, 14. Carbon nanotubes act as a filler material which reduces the thermal expansion coefficient of the Cu matrix. With the addition of CNTs the bulk electrical conductivity of the Cu composites can also be modified. Here we have used MWCNTs Synthesis of multiwalled carbon nanotubes (MWCNT) and development of Cu-MWCNT compositesHarshpreet Singh1, Lailesh Kumar2, Syed Nasimul Alam21 Department of Chemical and Materials Engineering, University of Auckland, New Zealand, 2 Department of Metallurgical and Materials Engineering, National Institute of Technology, RourkelaFigure 1 (a, b) Schematic of a typical CVD furnace setup used for the synthesis of MWCNTsFIGure 2 X-ray diffraction plot of MWCNTsab