MACHINABILITY EVALUATION OF CRYOGENICALLY TEMPERED DIE STEEL IN ELECTRIC DISCHARGE DRILLING

Shivnandan, Simranpreet Singh Gill

Abstract: Electrical discharge drilling (EDD) is a well-known machining alternative for creating geometrically obscure shapes in die steel. Cryogenic temper of work and electrode material is innovative technology in the field of EDD. Work in hand investigates the effect of cryogenic tempering of AISI D2 steel (workpiece) and copper electrode (tool) on material removal rate (MRR) in EDD based on design of experiments approach. The discharge current, pulse-on-time and electrode-workpiece combination (cryogenically tempered or untempered) are the parameters selected for this study. The orthogonal array, signal-to-noise ratio (S/N) and analysis of variance (ANOVA) are used to find out the effect of cryogenic tempering on MRR. The results obtained demonstrate that the discharge current and pulse-on-time are the major parameters influencing the MRR for all samples, followed by electrode-workpiece combination i.e. cryogenic tempering of electrode and workpiece. Cryogenic tempering is found to have significant effect (nearly 10%) on MRR. It is recommended to cryogenically temper both the electrode and workpiece to maximize the MRR

Keywords: Electric discharge drilling, Cryogenic tempering, Die steel, copper electrode

DOI: https://doi.org/10.15623/ijret.2013.0205023