ABSTRACT
The requirement of alloy materials with great hardness, strength and impact tolerance has been raised by the growth of the automotive sector to satisfy diverse needs. Therefore, non-traditional machining techniques such as electrochemical, ultrasonic and electrical discharge machining (EDM) are employed to machine materials that are too difficult to machine. Wire electric discharge machine (WEDM), which utilizes a wire electrode to initiate the sparking mechanism, is a special form of the traditional EDM process. AISI D2 steel finds numerous applications in die- and punch-making industry. Cryogenic-treated D2 steel and cryogenic-treated Bronco cut wire are never being used for the machining. Investigation of optimum parameters for cryogenic-treated and normal wire and workpiece is essential for comparing the results and checking the scope of cryogenic treatment in WEDM. Taguchi-based optimization is used in this work for finding optimum process parameters for machining of D2 steel. Operating parameters selected are (for normal and cryogenic-treated wire and workpiece) Ton, Toff, I, V and WT. The output parameter is selected as surface roughness. The conclusions of this experiment are minimization of surface roughness from 2.518 to 1.332 µm and cryogenic-treated workpiece shows minimum surface roughness at pulse-on time = 105 μs, pulse-off time = 45 μs, servo voltage = 15V and wire feed = 3 m/min.
