Experimental Investigation During Electrochemical Discharge Machining (ECDM) of Hybrid Polymer Matrix Composites

Silicon carbide particulates-reinforced polymer matrix composites have gained a reputation among composite materials due to their excellent mechanical properties. But these materials are categorized as hard to machine materials due to hardness and the abrasive nature of reinforcing particulates. For that purpose, it becomes necessary to develop a machining method which can be extensively used for machining of these types of materials. In this paper, an attempt has been made to optimize machining parameters of electrochemical discharge drilling process through response surface methodology. The experimentation was planned as per Box–Behnken design. Three process parameters, i.e. electrolytic concentration, voltage and inter-electrode gap were analyzed to explore their influence on output quality characteristics. The parameters voltage and inter-electrode gap are identified as most significant parameters for material removal rate and over cut, respectively. The surface plots were generated to study the effect of machining parameters as well as their interaction on output quality characteristics. The morphology of drilled hole was analyzed by scanning electron microscopy. A novel technique of measuring adjusted delamination factor (Fda) was adopted to analyze surface quality of machined zone. The analyzed results indicate that irregular damage pattern induced during drilling of composites can be effectively measured using adjusted delamination factor.