experimental investigation of the effect of deionized water on surface roughness of near dry electro discharge machining of aisi d2 steel

the electro discharge machining (edm), one of the methods used in the machining industry and a non-traditional manufacturing method, the electro erosion process does not depend on the hardness of material and offers a way to process materials of very complex geometry with very fine and high precision by using cheap electrode materials, which make it a preferred method. in this study, effect of wet and near dry edm has been investigated. design of the experiment was chosen as full-factorial. experimental data has been statistically analyzed and then appropriate model was extracted. the experimental results show that surface roughness decreases by increase of peak current and also pulse on-time; it should be mentioned that effect of peak current on surface roughness is greater than pulse on-time. also by using near dry machining (ndm), surface roughness decreased about 1µm and approximately 15 percent. these indicate the good performance of ndm.