Fabrication and Interfacial Bonding of CNT-reinforced Metal Matrix Composites

Recent advances in various engineering applications demand new materials that have multi-functionality along with suitable structural properties. Metal matrix composites are the class of materials that satisfy this purpose due to their lightweight, increased strength, and other improved mechanical properties. These composite materials can be prepared by various conventional techniques which aim reducing the cost of production and meeting the demand of the industries efficiently. The properties and functionality of these materials are greatly influenced by the type of reinforced particulates and their composition in the metal matrix. Many reinforcement particles or fibers can be used in MMC depending upon the applications. Commonly used reinforced materials are graphene, polymers, carbon fibers, ceramic materials, etc. Among the carbon family, carbon nanotubes (CNT) exhibit enhanced performance as an ideal reinforcement material for MMCs. With outstanding intrinsic physical properties, CNTs are considered a promising candidate for reinforcement. CNT owes its properties due to its small diameter, high tensile strength, stiffness, high Young’s modulus, and good chemical stability. They exhibit thermal stability even at high temperatures and exhibit good electrical conductivity. They also show improved fatigue resistance and plasticity and thus broaden the performance of the MMC. In this chapter, various fabrication techniques along with blending and processing methods of CNT-reinforced MMC have been discussed. The main methods have been explained with their schematic representations. The advantages and limitations of these methods have also been discussed. A strong interfacial bonding between the reinforced particulate and the metal matrix affects the performance of the material. This chapter also deals with a deep understanding of the various interfacial bonds that can exist between CNT and the metal matrix

Keywords: Bonding interface, Carbon nanotubes, Mechanical properties, Metal matrix composite, Reinforcement effect, Solid state processing.