33. Optimization of Process Parameters on Performance Measures of Wire Electrical Discharge Machining on Niobium C-103 Using Taguchi Method

The requirement for high accomplishment, lightweight, space propulsion systems has prompted rapid investigation of refractory metals that are capable of withstanding high stress levels at elevated temperatures. It also has a low ductile-to-brittle transition temperature for withstanding high-frequency vibrations at cryogenic temperatures. Metals which demonstrate these requirements are the niobium-based alloys. C-103 was selected to satisfy initial design requirements because of its excellent fabric ability. As of human nature which wants continuous improvement, we need such materials which have lesser density and high melting temperature than superalloys. Refractory metals and the alloys are the only alternative to meet the properties which are more superior to super alloys. These have high melting temperature above 2000 °C and low density compared to superalloys. Among these refractory metals, niobium is least dense. Due to this, alloy of niobium like C-103 is gaining popularity in aerospace industry and rocket engines. In the present study, the effect of input parameters, pulse-on time T_ON, pulse-off time T_OFF, peak current IP and servo voltage SV on output parameters surface roughness SR, and metal removal rate MRR are studied while machining with brass and Zn-coated brass wires in WEDM. T_ON is the most significant parameter to influence SR, and peak current is most significant parameter for MRR. Zn-coated brass wire is giving less SR and more MRR as compared to brass wire.