Experimental Investigation on Al2O3 Ceramics by Powder Mixed Electrochemical Discharge (PM-ECDM) Process

Electrochemical discharge machining is a non-conventional machining technique for machining electrically non-conducting materials like glass, quartz, ceramics, and composites. Spark generation and control of gas bubbles around the tool has been a major problem in many researches. This work aims towards possibility of improving the material removal rate (MRR) and reduction of diametric over cut (DOC) by adding graphite powder to the electrolyte. The most effective values for machining parameters have been analyzed using the Taguchi S/N ratio analysis. Maximum MRR is obtained at high level of applied voltage, duty factor and concentration of electrolyte and moderate level of concentration of powder. Similarly the minimum DOC is obtained at low level of applied voltage and duty factor and moderate level of concentration of electrolyte and concentration of graphite powder between 3- 4 wt%. Confirmation test with optimal level of process parameters is carried out to validate the obtained optimum value.