Direct Metal Laser Sintering (DMLS) is a powder-bed additive manufacturing technology capable to produce fully dense metal parts layer-by-layer from a 3D cad model. The consolidation and the properties of the metal components strongly depend on each laser melted track. In this study, the effects of the building parameters, such as laser power and scan speed, on the shape and the microstructure of a single scan track has been evaluated. Powders of AlSi10Mg and its composites have been laser scanned in order to appreciate the effect of the powders properties on the phenomena that arise in the melt pool such as the balling effect and the spreading of the molten phase. The experiments were carried out in argon atmosphere on an AlSi10Mg platform with fixed laser spot (100 ?m) and building platform temperature (100 °C).