Electrical discharge machining, Aluminum alloys, Surface topography, Surface roughness, Peak current, Pulse-on time


Electrical discharge machining is one of the most important non-conventional machining processes for removing material from electrically conductive materials by the use of controlled electric discharges. EDM is a non-contact machining process, therefore, is free from mechanical stresses. This paper investigates the machining Al7075-T6 alloy by EDM using a copper electrode. Al7075-T6 alloy was selected, because of its growing use in a lot of engineering applications. The effect of electrical parameters, peak current and pulse-on time, on the surface integrity, was studied. Area surface roughness parameters (arithmetical mean height, Sa, and maximum height, Sz) were measured on all samples and 3D surface characterization has been carried out with confocal laser scanning microscopy. The experimental results showed that the surface roughness is mainly affected by the pulse-on time.

Author Biographies

Maria Balanou, National Technical University of Athens, (NTUA)

PhD Student, National Technical University of Athens (NTUA), Department of Manufacturing Technology, Greece

Lazaros-Emmanouil Papazoglou, National Technical University of Athens, (NTUA)

PHD Student, National Technical University of Athens, (NTUA), Greece, Department of Manufacturing Technology,

Master of Science 

Angelos P. Markopoulos, National Technical University of Athens, (NTUA)

Professor, National Technical University of Athens (NTUA), Greece,  Department of Manufacturing Technology

Panagiotis Karmiris-Obratański, AGH University of Science and Technology in Kraków, Poland

AGH University of Science and Technology in Kraków, Poland, Master of Engineering, Doctorant  Doctoral Schools


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Mechanical processing of materials, the theory of cutting materials, mathematical and computer simulation of machining p