toward sustainable machining: a comprehensive review of surface modification techniques for cutting tools

Cutting tools are subjected to severe wear during machining operations, especially when processing hard-to-machine materials. this wear primarily results from the intense friction and heat generated at the tool–chip–workpiece interfaces. to mitigate these effects and extend tool life, numerous strategies have been developed to modify the rake and flank surfaces of cutting tools. these include surface texturing and advanced coating techniques aimed at enhancing tribological properties, chemical stability, and resistance to mechanical stresses. this review provides a comprehensive analysis of such surface modification methods, highlighting their role in reducing friction, minimizing tool wear, and improving cutting efficiency. a detailed classification of cutting tool materials, such as ceramics, carbides, and polycrystalline cubic boron nitride used in recent studies for machining hard materials is presented. the paper also identifies current challenges and research gaps, particularly in the context of superalloy machining. finally, it outlines promising future directions, including the development of functional tool surfaces, integration of data-driven optimization approaches, and the exploration of novel tool materials and geometries. the overarching aim is to promote sustainable, cost-effective, and high-performance machining practices aligned with modern manufacturing demands.