Machining of FRP Composites: Surface Quality, Damage, and Material Integrity: Critical Review and Analysis

Composite materials particularly fiber-reinforced plastics (FRPs) have brought remarkable advances in various engineering sectors because of their excellent mechanical properties. Ranging from space applications to consumer products, their demand is ever increasing, and to bridge this supply gap, constant endeavor is focused on optimizing their production rate. Numerous conventional and nonconventional processes are employed for manufacturing and machining these FRPs. Every day novel technologies are explored to make the production of FRPs much agile. FRPs are always manufactured to near net shape; however, functional assemblies demand minimal machining post manufacturing. The real challenge lies here as FRPs are difficult to machine due to their intrinsic anisotropy, fragility, and inhomogeneity. Abundant research done on conventional and nonconventional machining reveals that machining alters the surface characteristics and induces damage in FRPs. Researchers have demonstrated that machining parameters have great influence on the extent of surface degradation and damage, and have suggested several measures to improve the machining quality. Surface degradation and damage induced have a notable influence on the material integrity which may be inferior to the expected values, thus decreasing the reliability of the machined component. This chapter presents the readers a comprehensive review of various machining processes of FRPs focusing on the multilevel surface and damage characteristics, as well as their impact on the mechanical behavior. It shall help the designer of composite structures to understand the correlation between the machining processes, surface integrity, damage, and the mechanical properties induced in order to reduce the cost for the manufacturing during the design phase.