Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Response Surface Methodology

Effect of Powder-Mixed Dielectric on EDM Process Performance

Safa R. Fadhil; Shukry H. Aghdeab

Engineering and Technology Journal, 2020, Volume 38, Issue 8, Pages 1226-1235
DOI: 10.30684/etj.v38i8A.554

Electrical Discharge Machining (EDM) is extensively used to manufacture different conductive materials, including difficult to machine materials with intricate profiles. Powder Mixed Electro-Discharge Machining (PMEDM) is a modern innovation in promoting the capabilities of conventional EDM. In this process, suitable materials in fine powder form are mixed in the dielectric fluid. An equal percentage of graphite and silicon carbide powders have been mixed together with the transformer oil and used as the dielectric media in this work. The aim of this study is to investigate the effect of some process parameters such as peak current, pulse-on time, and powder concentration of machining High-speed steel (HSS)/(M2) on the material removal rate (MRR), tool wear rate (TWR) and the surface roughness (Ra). Experiments have been designed and analyzed using Response Surface Methodology (RSM) approach by adopting a face-centered central composite design (FCCD). It is found that added graphite-silicon carbide mixing powder to the dielectric fluid enhanced the MRR and Ra as well as reduced the TWR at various conditions. Maximum MRR was (0.492 g/min) obtained at a peak current of (24 A), pulse on (100 μs), and powder concentration (10 g/l), minimum TWR was (0.00126 g/min) at (10 A, 100 μs, and 10 g/l), and better Ra was (3.51 μm) at (10 A, 50 μs, and 10 g/l).

Enhancement of Surface Crack Density Produced by EDM Using Hybrid Machining

Saad K. Shather; Shukry H. Aghdeab; Waqass S. Khudier

Engineering and Technology Journal, 2019, Volume 37, Issue 12A, Pages 566-573
DOI: 10.30684/etj.37.12A.11

The present work is aimed to improve the surface cracks density of electrical discharge machining (EDM) by Electrical Discharge Machining (EDM)/Electrochemical Machining (ECM) EDM/ECM hybrid process. A hybrid method of EDM-ECM combined processing involve EDM shaping as well as electrochemical machining (ECM) finishing, also, they are conducted in sequence one same machine tool, same electrode, yet on the different dielectric. In this study, the used workpiece material is the A2-Tool Steel material, while the electrode material is copper. The influence of controllable parameters could be identified via response surface methodology (RSM), these controllable effects include: pulse current, pulse on time, pulse off time, gap, voltage, and electrolyte concentration on surface cracks density (SCD). It has been noticed that model has been developed by RSM adequacy is acceptable because the coefficient of determination is closest to one for SCD, whereas the optimal solution achieved by Desirability Function Analysis (DFA) are (current =42 A, pulse-on time =100 , and pulse-off time =50 )in addition to that, the generated surface doesn’t have any crack which has been generated via EDM are removed entirely through ECM finishing.