Investigation on manufacturing of microtools made of tungsten carbide using wire electric discharge grinding (WEDG)

Wire electric discharge grinding has been developed to generate cylindrical profiles on hard-to-machine microparts. The outcome of the part is influenced by the process conditions and the rotational speed of the spindle. This paper investigates the effects of machining parameters on material removal rate (MRR), surface roughness and circularity during wire electrical discharge grinding process of tungsten carbide workpiece. Experiments have been carried out by varying process conditions such as peak current, open circuit voltage, pulse off time, servo voltage and number of passes. Pulse current has the highest significance to obtain maximum MRR. To obtain the best surface quality, pulse current, number of passes and pulse off time are identified as the most significant parameters. Using the technique of order preference by similarity to ideal solution, the optimal conditions estimated are pulse current (38 A), open circuit voltage (60 V) and pulse off time (24 mu s) for finish machining.