Deposition and Analysis of Composite Coating on Aluminum Using Ti-B4C Powder Metallurgy Tools in EDM

The present work investigates the method of depositing a ceramic coating on the surface of aluminum by means of electrical discharge coating (EDC) in electrical discharge machining (EDM). The present study makes use of powder metallurgy (P/M) green compacts made of titanium, boron carbide, and aluminum (Ti+B4C+Al) powder as the EDM tool for surface modification of aluminum workpieces. EDM process was carried out with different tool parameters like composition of the electrode material, compaction pressure of the green compacts, and different settings of the process variables like peak current and pulse duration setting. Responses observed were material deposition rate (MDR), tool wear rate (TWR), and average layer thickness (LT). Experiments were designed and carried out using Taguchi L-18 orthogonal array. The most influential parameter for responses MDR, TWR, and LT was found to be peak current (I-p) with a percentage contribution of 60.72%, 59.52%, and 42.09%, respectively. In addition, various other characterization techniques such as optical microscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectrum (EDX) analysis were performed in order to judge different attributes of the deposited coating.