One of the main limiting factors for a widespread industrial use of the Selective Laser Melting Process it its lack of productivity, which restricts the use of this technology just for high added-value components. Typically, the thickness of the metallic powder that is used lies on the scale of micrometers. The use of a layer up to one millimeter would be necessarily associated to a dramatic increase of productivity. Nevertheless, when the layer thickness increases, the complexity of consolidation phenomena makes the process difficult to be governed. The present work proposes a 3D finite element thermo-coupled model to study the evolution from the metallic powder to the final consolidated material, analyzing specifically the movements and loads of the melt pool, and defining the behavior of some critical thermophysical properties as a function of temperature and the phase of the material. This model uses advanced numerical tools such as the Arbitrary Lagrangean–Eulerian formulation and the Automatic Remeshing technique. A series of experiments have been carried out, using a high thickness powder layer, allowing for a deeper understanding of the consolidation phenomena and providing a reference to compare the results of the numerical calculations.

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Electro Discharge Machining is no longer taken as a ''force free'' process. Studies are being completed in order to understand how these forces are being exerted on the electrodes and how they might affect the processing of highly precise or high aspect ratio geometries. This paper studies process forces on macro Sinking-EDM with the use of two highly precise piezoelectric axial force sensors which measure single discharge forces simultaneously at the tool and workpiece sides. At the same time, the vibration amplitude and frequency of tool electrodes are measured, along with the analysis of high-speed-camera photographs showing a chronological sequence of gas bubble formation in terms of their dilatation and collapse, allowing a more detailed view into the process. The understanding of the dynamic trends of these process forces allows drawing conclusions about the generation of the pressure field along the working gap and its influence on tool electrode vibration which can decrease the final desired precision of the manufactured workpiece.

The production of micro-parts often involves micro-milling and micro-EDM operations. Although both processes are competitive for certain geometries, each of both processes has its specific advantages. Driven by the current trend of hybridization of machining processes it is important to know which process or which combination of processes to use in order to attain a certain performance level. Therefore this paper compares micro-milling and micro-EDM operations specifically for the machining of rectangular shaped geometries. The comparison is based on several performance parameters like dimensional and geometrical accuracy, surface roughness, machining time and energy consumption. This initial study shows that for the considered geometries a comparable dimensional accuracy can be obtained for both processes. Besides this it is shown that micro-milling excels micro-EDM in terms of flatness of the bottom surface, surface roughness and machining time. On the contrary, micro-EDM gives better performance in terms of straightness of the walls and energy consumption. Based on these results combined machining strategies are proposed which make use of the advantages of both processes.