The feasibility analysis of electrical-discharge machining of carbon-carbon composites

The objective of this research is to investigate the feasibility of using Electrical-Discharge Machining (EDM) for carbon-carbon composite materials as well as the effects of major machining parameters. The material was machined by electrical-discharge sinker using copper electrode. The mechanism of material removal has been revealed by the morphology of debris. The material removal rate, the surface topography and the recast layer that remains on the workpiece surface were studied in terms of EDM processing variables (e.g., pulse current and pulse duration time). The machined surface showing resolidification was examined by Scanning Electron Microscopy (SEM). A qualitative energy dispersive spectroscopic analyzer was used to measure the amount of migrated alloy in the workpiece and the chemical composition of recast layer. The machining damage, the recast layer, and the mass transfer was proportional to the power input. The EDM process is a feasible method for machining of carbon-carbon composites.