5. Metal Matrix Composites

Composite materials, or in their short-form composites, are a specific category of materials in which two or more materials, as constituents or ingredients, with considerably dissimilar physical or chemical properties are combined together to achieve unique characteristics that might be quite different from those of individual components. In composite materials, the constituent materials remain distinct within the final structure. One of the constituents acts as the main body, which forms the bulk of composite. The main body surrounds and supports the other constituent that usually acts as the strengthening or reinforcing element. Between the two elements, the former is called matrix while the latter is named reinforcement. If the matrix is made of a metallic material, the resultant composite is called metal matrix composite or in short MMC. The reinforcement can be of any metal or other types of materials such as ceramics or organic compounds. Composite materials usually have distinguished physical properties that cannot be found combined in traditional materials. The current chapter explores the composite materials, especially MMCs with the main focus on the challenges that might be encountered during machining of these advanced materials. It presents a brief review of composites’ history of evolution, their unique characteristics, and their mechanical properties. Cutting characteristics, appropriate tool materials, modes of tool wear, and other influential factors that must be taken into consideration when machining composite materials will also be presented in this chapter. The chapter ends with an overview of the challenges associated with machining reinforced fiber composites.