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Purpose - Therefore, the purpose of this study is to understand the relationships between the processing parameters and the geometric form of the produced single tracks, in order to control dimensional quality in future experimentations. The quality of the deposited single track and layer is of prime importance in the selective laser melting (SLM) process, as it affects the product quality in terms of dimensional precision and product performance. Design/methodology/approach - In this paper, a vertical milling machining center equipped with an Ytterbium-fiber laser was used in the SLM experimentation to form single cobalt-chromium-molybdenum (CoCrMo) tracks. The different geometric features and the influence of the scanning parameters on these morphologic characteristics were studied statistically by means of ANOVA. Findings - Evidently, track height (h1) inaccuracy reduced in layer thicknesses between 100 and 200 μm. The re-melt depth (h2) was determined by the energy parameters, with laser power of 325-350 W and scanning speed (SS) of 66.6-83.3 mm/s being the most favorable parameters to obtain the required anchoring. Moreover, a contact angle of 117° was proposed as optimal, as it permitted an adequate overlapping region and a full densification, and, finally, an SS of 50 mm/s and a layer thickness of 250 were suggested for its development. Originality/value - The comprehension of the phenomena inherent to the process is related to the single track geometrical characteristics, which allow the definition of an optimal value for each factor for a further proposal of processing conditions that can finally derive a higher precision, wetting, density and mechanical propertiesThe authors gratefully appreciate the financial supports from the Spanish Government (project DPI2009-09852) and the European Union Seventh Framework Programme (FP7-PEOPLE-2009) under the grant agreement IRSES n° 247476 that lead to these research result

Selective Laser Melting (SLM) is an additive technology that produces solid parts by selectively melting thin layers of metallic powder. SLM can produce significant differences in the final properties due to the melting-consolidation phenomena of the process, which can be controlled by the appropriate parameters. Therefore, the objective of this study was to create a link between the process conditions and the resulting properties by experimenting in an own-developed SLM machine using CoCrMo powder as material. The fabricated samples were characterized by density, hardness and microstructural properties. The experimental results proved the capability of the SLM technique to build high dense samples. The hardness results gave evidence of a superior outcome compared to conventional processes. Finally, it was found that grain size was defined by scanning speed. Based on the results, a better understanding of the processing principles given by the parameters was achieved and improved fabrication quality was promotedThe authors gratefully appreciate the financial support from the European Union Seventh Framework Programme (FP7-PEOPLE-2009) under the IRSES n 247476 grant agreement, which led to these research result

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