Analysis of the effect of material thickness during the WEDM processon cutting speed, topography and morphology

Abstract

Wire electrical discharge machining (WEDM) is an unconventional machining technology that is indispensable in many industries. Machining is performed using the thermoelectric principle, while it is possible to machine all at least minimally electrically conductive materials. Due to the wide range of applications of WEDM, it is necessary to ensure the appropriate quality of machined surfaces, regardless of the thickness of the machined materials, while maintaining an acceptable cutting speed. For this purpose, this study was performed to analyse the effect of material thickness on the cutting speed, morphology and topography of Ampcoloy 35 material. In this study, thicknesses from 5 to 160 mm were analysed in 5 mm increments with the same machine parameter settings. The surface topography and morphology were studied using electron and light microscopy, and cross-sections of the sample were created to examine the condition of the subsurface layer. It was found that the values of Ra at the edge ranged from 1.8 to 3.2 µm and in the middle of the sample from 1.7 to 3 µm, while the trend of increasing Ra with thickness is not visible. It is clear from the morphology analysis that a rugged surface with more craters was created at the edges than in the middle of the sample, while segregated lead needles were also formed at the edges of the samples.