Influence of the aspect ratio of an additive manufacturing component on the surface roughness during cutting with wire EDM

Aluminum alloy AlSi10Mg is among the most used alloys in powder bed additive technologies with laser source (PBF-LB/M) to make light components in sectors such as aerospace and automotive. These components can have complex shapes and are made in some extrusions directly on the construction platform in order to remove them by wire electrical discharge machining (WEDM) and obtain a surface roughness already suitable to be able to assemble the parts with other components. This study investigated two aspects: the robustness of different instruments for profile and areal roughness measurements on AlSi10Mg parts produced by the PBF-LB/M process; and the effect of the aspect ratio of the components on the surface roughness obtained from WEDM. A better correspondence between the P- and S-parameters was found than that reported in the literature between the S- and R-parameters. Analyzing the relationship between weight and height of the AlSi10Mg components, the results showed that the heaviest and tallest component presents the least roughness (Ra = 5.05 ± 0.63 μm and Rz = 33.11 ± 4.29 μm). However, it emerged that the various areas of the piece have different roughness values (from Ra = 7.65 ± 2.85 μm and Rz = 43.07 ± 13.12 μm to Ra = 15.21 ± 7.37 μm and Rz = 68.39 ± 25.75 μm) of and this requires constant adjustment of the cutting parameters to have uniform surface roughness.