15-11-2014, 02:46 PM
Abstracts: At present Industrial application needs the use of advanced materials like tool steels, super alloys, ceramics, and composites with high precision and high surface quality. These materials are hard and difficult to machine. To meet these challenges, nonconventional machining processes are being employed to achieve higher metal removal rate, better surface finish and greater dimensional accuracy. Wire electric discharge machining (WEDM) is a specialized controlled discrete spark erosion non-conventional machining process capable of accurately machining parts having complex shapes irrespective of material hardness. WEDM becomes a competitive and economical machining option which fulfills the requirement of short product development cycle. This process is affected by so many control parameters. WEDM is a complex machining process controlled by a large number of process parameter such as Pulse duration, Specific energy, discharge frequency and discharge current intensity. For optimal machining performance the setting of various input parameters plays a crucial role on output viz. Material removal rate, Surface roughness, Little change in one parameter greatly affect the output. Hence process parameter optimization needs for variety of material. In present an attempt is made to investigate the effect of varying pulse on time, pulse off time, flushing pressure, servo voltage and wire tension on SS 304 material to analyze effect on the Material Removal Rate and Surface finish using Taguchi analysis and multi response grey Taguchi base optimization will be carried out. A Taguchi design of experiment (DOE) approach with L9 Orthogonal Array employed to conduct this experiment. MiniTab15 software was used to perform the Taguchi (analysis of Variance) and confirmation test conducted to verify as well as compare the results from the theoretical prediction using software. Multi response optimization carried out using Gray relational Grade method. Overall result shows that MRR increases with increasing Pulse On time and decreases with increasing Pulse Off time. Significant factor for Surface roughness are Material Thickness, Pulse on Time, Wire Tension and Servo voltage. Material thickness has little effect over MRR but has significant effect on surface roughness. Higher flushing pressure needs for better MRR and Surface finish.