WEAR ANALYSIS OF DEEP CRYOGENIC TOOL ELECTRODE DURING ECDM OF CFRP COMPOSITE

Electrochemical Discharge Machining (ECDM) is broadly accepted for the machining of both conductive and non-conductive materials. However, the tool wear during machining significantly affects the process accuracy. An attempt has been made to explore the behavior of the tool variables, such as tool rotation, tool feed rate, tool immersion depth, and cryogenic-treated tool on tribological parameters, viz., axial tool wear during ECDM of carbon fiber-reinforced polymer composite. Experiments are conducted using a tool rotation of 500–700[Formula: see text]rpm, a tool travel rate of 200–400 [Formula: see text]m/min, and a tool immersion depth of 1–2[Formula: see text]mm, with deep cryogenic-treated and non-treated tool electrodes. The tool wear dominantly decreases with increases in tool rotation, tool feed rate, and tool immersion depth during machining. The surface characteristics of the tool and the machined hole were investigated using scanning electron microscopy (SEM). SEM micrographs clearly illustrate a significant reduction in axial tool wear, with deep cryogenic-treated electrodes exhibiting 90 [Formula: see text]m of axial wear compared to 1640 [Formula: see text]m for untreated electrodes, reflecting an improvement of approximately 95%. Additionally, machining accuracy is enhanced, as indicated by an 11% reduction in both overcut (from 350 [Formula: see text]m to 310 [Formula: see text]m) and taper (from 44 [Formula: see text]m to 39 [Formula: see text]m) in the machined hole. These improvements highlight the effectiveness of deep cryogenic treatment in enhancing tool performance and precision. From a tribological perspective, the improved wear resistance of the cryogenically treated tool electrode reduces frictional losses, leading to enhanced machining accuracy and prolonged tool life. Therefore, a deep cryogenic-treated tool electrode with parametric conditions of a tool rotation speed of 700[Formula: see text]rpm, a tool travel rate of 400 [Formula: see text]m/min, and a tool immersion depth of 2[Formula: see text]mm is highly recommended for the micro-machining of carbon-reinforced polymer composite.