Review on Surface Modification and Coating Effects in Wire EDM Machining Performance

Wire Electrical Discharge Machining (WEDM) is a widely adopted process for producing intricate and high-precision components where conventional machining methods face limitations. The performance of WEDM is strongly influenced by the properties of the wire electrode, with coated and surface-modified wires offering significant advantages over plain brass wires. This review systematically examines advancements in wire surface modification, from conventional zinc coatings to diffusion-annealed, nano-engineered, and composite structures. Reported improvements include higher material removal rates, reduced surface roughness, superior wear resistance, and greater dimensional stability. Despite these advances, critical gaps remain, particularly in the absence of standardized benchmarking protocols, comprehensive life-cycle and techno-economic evaluations, and scalable fabrication methods. Furthermore, sustainability aspects such as recycling, environmental footprint, and large-scale industrial validation are underexplored. Addressing these limitations will be essential to translate laboratory-level innovations into robust industrial solutions and to ensure the broader adoption of coated wire technologies in advanced manufacturing sectors.