Machining of aluminium based metal matrix composites

Although metal matrix composites (MMCs) are generally regarded as extremely difficult to machine, it is also acknowledged that their machining behaviour is not fully understood. The work reviewed here confirms this widely held view but also suggests that the machinability of these materials can be improved by appropriate selection of the reinforcing phase, its volume fraction, size, and morphology as well as the composition and hardness of the matrix material. Cemented carbide tools can be used to machine some of the less abrasive materials at slow speeds but if higher production rates are required or the more abrasive materials are to be machined, polycrystalline diamond tooling is required.