Optimization of EDM conditions in the manufacturing process of B4C and WC-Co conductive ceramics

Technical or advanced ceramics have achieved a great deal of importance nowadays as a consequence of their outstanding properties, which make them suitable for application to high-resistance dies and tools for drilling, metal forming and structural components, among others. Nevertheless, manufacturing of these materials is difficult and expensive because they are hard-to-machine materials. In this present study, the application of Electrical Discharge Machining (EDM) is explored for the processing of two conductive ceramics: hot-pressed boron carbide (B4C) and cobalt-bonded tungsten carbide (WC-Co). The main aim of this present study is to analyse the influence of intensity (I), pulse duration (ti), duty cycle (η), open-circuit voltage (U) and dielectric flushing pressure (P) on the quality of these manufactured products. The response variables studied are: surface roughness (Ra), volumetric electrode wear (EW) and material removal rate (MRR). This study has great industrial interest as there seems to be a lack of knowledge of die-sinking EDM of conductive ceramics in comparison with metallic materials.