Energy-controlled Micro Electrical Discharge Machining for an Al2O3-carbon Nanotube Composite

Carbon nanotube (CNT) and alumina (Al2O3) are synthesized into hybrid composites, and an advanced electrical discharge machining (EDM) system is developed for the machining of hard and conductive materials. CNT nanoparticles are mixed with Al2O3 powder and the Al2O3/CNT slurry is sintered by spark plasma. The hardness and the electrical conductivity of the Al2O3/CNT hybrid composite were investigated. The electrical discharge is controlled by a capacitive ballast circuit. The capacitive ballast circuit is applied to the tungsten carbide and the Al2O3/CNT hybrid composite. The voltage-current waveforms and scanning electron microscope (SEM) images were measured to analyze the characteristics of the boring process. The developed EDM process can manufacture the ceramic based hybrid composites, thereby expecting the variety of applications.