Electrical Discharge Drilling of Al-Sic Composite Using Air Assisted Rotary Tubular Electrode

Abstract

Hybrid machining process (HMP) is an integration of two or more machining process. HMP is used to machine hard materials that cannot be machined effectively by the individual machining process. This work focus on developing a hybrid process using both liquid and gas as dielectrics to study its effect on tool wears rate (TWR) and material removal rate (MRR). The compressed air passing through a rotary tubular electrode removed and flushed out the debris from the inter-electrodes gap and hence it improves the flushing efficiency and stability of the process. In this study, the selected workpiece material was Al-15% SiCp MMC. Silicon carbide is selected as filler material in MMC. Experiments have been carried out following the Taguchi design of experiments. The influence of various machining parameters on MRR, TWR, and optimization of process parameter has been performed. Under the same machining condition, high MRR and low TWR obtained when hybrid EDM machining was done as compared to conventional EDM machining. Experimental findings suggested that supply of compressed air through rotary tubular electrode in die sinking electrical discharge machining have a positive influence on MRR and TWR.