The influence of cut direction and process parameters in wire electrical discharge machining of carbon fibre–reinforced plastic composites

Abstract The paper details a comprehensive experimental investigation on the influence of operating parameters and cut direction (parallel perpendicular to fibre orientation) when wire electrical discharge machining (WEDM) unidirectional CFRP composites using zinc-coated brass (0.25-mm diameter). A Taguchi L18 fractional factorial orthogonal array considering four variable including open voltage, ignition current pulse-on time as well pulse-off was carried out for each direction. Results showed that ~ 16% increase in maximum material removal rate achieved parallel (2.41 mm 3 /min) compared cutting fibres (~ 2.08 /min), which attributed higher conductivity workpiece along length leading greater energies. This however resulted relatively larger average kerf widths poorer surface roughness (Sa) caused by Joule heating effect. Workpieces machined were generally free any major edge defects, contrast severe delamination observed both top bottom surfaces specimens orientation. High-magnification scanning electron microscopy revealed presence adhered resin material, cracking, cavities/gaps matrix phase interlayer cracks most samples analysed, with damage severity dependent