A review on mechanical micro-machining of polymeric materials

Official URL: https://dx.doi.org/10.1016/j.jmapro.2026.03.043

Polymeric materials are replacing metals in applications due to their biocompatibility, corrosion resistance, low density, and design flexibility, especially in biomedical and automotive components. Reinforcements have improved mechanical and thermal properties, but they have reduced machinability, making machining processes difficult. Although polymer components are usually produced near-net shape, secondary machining is often needed to meet dimensional and assembly requirements, and can be more cost-effective than molding for low-volume production. The development of miniaturized products, due to increased efficiency, improved mobility, reduced energy consumption, and reduced weight, has increased the importance of micro-machining processes like micro-drilling, micro-milling, and micro-turning. Unlike conventional machining, micro-machining processes are significantly influenced by the size effect, in which cutting edge radius, minimum chip thickness, and material microstructure play an important role in machining. These factors have made machining processes in polymers and composites very difficult. This review critically discusses mechanical micro-machining processes in polymeric materials and composites, particularly machining processes, problems, and material properties' effects on machinability. Emphasis has been given to reinforcement materials, tool wear, and machining parameters. Machining processes in polymers have improved, and problems like tool wear, surface integrity, and delamination are still significant problems in machining processes. Future research should be directed toward optimizing machining processes in machining complex geometries, improving lubrication, and exploring new materials and methods in machining processes.