Effect of Process Parameters on Spark Energy and Material Removal Rate in Electro-Discharge Machining Process

Abstract

Electro-discharge machining process is a very important non-traditional, cost-effective and non-contact technique of machining electrically conductive materials which are extremely tough, brittle and difficult-to-cut. The material removal takes place electro thermally with the help of several discrete discharges between the work and the electrode. It is used to manufacture complex geometries and intricate shaped sections with very high accuracy. The material removal rate and spark energy both depend on the input process parameters in this process. The efficiency of the machining process can be maximized by optimizing the input process parameters. The material selected for this study was Inconel-925. In this work the effects of input parameters like pulse on time, current and voltage were studied on the metal removal rate and spark energy by applying the sensitivity analysis. This was performed by taking two input parameters as fixed and the third one as varying for all the three input variables. The variations were tabulated, and the graphs were drawn to understand the effect of individual input parameters on the metal removal rate and spark energy. After the sensitivity analysis it was found that metal removal rate in electro-discharge machining process increases with increase in current, increases nonlinearly with increase in voltage and increases with an increment in pulse on time up to a certain limit and then keeps on decreasing.