Electro chemical discharge machining and optimization of non-conducting materials

Abstract

Electro Chemical Discharge Machining Process (ECDM) is an emerging hybrid machining process used in precision machining of hard and brittle nonconducting materials. ECDM has been utilized to fabricate micro-holes in non-conductive brittle materials. An experiment has been conducted on ECDM for micro drilling operation on borosilicate glass material according to the Taguchi Orthogonal Array (L9) technique in order to identify the effect of certain parameters such as material removal rate (MRR) and tool wear rate (TWR). In controlling the machining performance, signal to noise ratio (S/N ratio) was calculated to find out the contributions of the main machining parameters, such as applied voltage, electrolyte concentration and inter electrode gap. During the experiments, the non-conducting and highly brittle borosilicate glass material is used as a work-piece and NaOH as electrolyte solution. In addition to that, Graphite and Tungsten were used as cathode and anode respectively. In this study, Taguchi method was employed to optimize the process parameters which affect MRR and TWR. From main effect plot through Minitab software, it has been found that the inter-electrode gap has the greatest impact on MRR and TWR.