Abstract

Electrical discharge machining (EDM) is an attractive machining technique but it requires electrically conductive ceramic materials. In this study, Alumina matrix composites reinforced with CNTs were fabricated through CNT purification, mixing, compaction and spark plasma sintering (SPS) processes. Al_2O_3 nanocomposites with the different CNT concentrations were synthesized. The mechanical and electrical characteristics of Al_2O_3/CNTs composites were examined in order to apply the materials to the EDM process. In addition, micro-EDM using wire electrical discharge grinding (WEDG) was conducted under the various EDM parameters to investigate the machining characteristics of machined hole by Field Emission Scanning Electron Microscope (FE-SEM). The results show that Al_2O_3/CNTs 10%Vol. was more suitable than the other materials because high conductivity and large discharge energy caused violent sparks resulting in bad machining accuracy and surface quality.

• Keywords: Conductive ceramic;Al_2O_3/CNTs hybrid composites;Micro EDM;WEDG device;