Study the Effect of Electrical Current on Average Surface Roughness of Borosilicate Glass at EDM Machining and Comparison Using Matlab Program

Abstract

Machining of electrically non-conducting materials like glass is still a majorproblem. The principle of electric arc was used to generate high electricaldischarge (spark) at high currents to machine non-conducting materials at anyhardness.EDM system was build for machining of non-conducting cutting materialssuch as glass including the use of powder (graphite) mixed for dielectric solution(tap water) by supplied DC current values (200, 250, 300, 350 and 400A). Voltageof (70V) was used to cut 3mm thickness of borosilicate glass (BSG) to obtain theaverage surface roughness (Ra) of about (0.003-0.012μm).Matlab program has been used to investigate the process control for EDM thatcould the Ra experimental and theoretical with accuracies of 94.236, 94.034,96.628 and 92.875% respectively.From the reading of the magnitude of the roughness it was found that differencesbetween the theoretical and experimental values for 3mm thickness of BSG wasnever exceed (8%).