Influence of Polarity of Electro Discharge Machine (EDM) on Surface Roughness (SR) and Metal Removal Rate (MRR) of Low Carbon Steel

Taqi, Shahd; Shather, Saad K.

doi:10.30684/etj.v38i7A.469

	Influence of Polarity of Electro Discharge Machine (EDM) on Surface Roughness (SR) and Metal Removal Rate (MRR) of Low Carbon Steel
Engineering and Technology Journal
Article 4, Volume 38, 7A, 2020, Pages 975-983 PDF (1.04 M)
DOI: 10.30684/etj.v38i7A.469
Authors
Shahd Taqi^* ¹; Saad K. Shather²
¹Production Engineering and Metallurgy Department., Baghdad, Iraq
²Production engineering and metallurgy department, university of technology, Baghdad, Iraq.
Abstract
Electro discharge machining (EDM) is one of a thermal process that is used for remove of metal from the workpiece by spark erosion. The work of this machine depends on multiple variables. One of the more influential variants on this machine is the change of polarity and the use of this variable is not wide and the research depends on the polarity of the machinist. Essentially, the polarity of the tool (electrode) is positive and the workpiece is negative, this polarity can be reversed. This paper focuses on the influence of changing the polarity (positive and negative) on the surface roughness and metal removal rate by using different parameters (current, voltages, polarity and Ton). Experiments show that the positive electrode gives (best surface roughness = 1.56 μm when the current = 5 Am and Ton = 5.5 μs) and (best metal removal rate = 0.0180 g/min when the current = 8 Am and Ton = 25 μs). Negative electrode gives (best surface roughness = 0.46 μm when the current = 5 Am and Ton = 5.5 μs) and (best metal removal rate = 0.00291 g/min when the current = 8 Am and Ton = 25 μs).
Keywords
EDM; Polarity; MRR; Surface roughness (Ra)

References
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