PSI - Issue 8

P. Conti et al. / Procedia Structural Integrity 8 (2018) 410–421 Author name / Structural Integrity Procedia 00 (2017) 000–000

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4. Conclusions This work presented represents an attempt to model additive manufacturing and to forecast the performances. The specific heat dependence and thermal conductivity from the temperature have been greatly simplified; these simplifications make the model a useful tool for assessing the influence of individual parameters and comparison of different settings of project parameters although not very accurate. All the results are purely numeric and therefore an experimental is test program required to correctly tune the FE model. An observation concerns the model of the heat source; the effect of the Gaussian distribution in our model is not significant because the laser area affects at most sixteen elements and only four elements at a time are completely illuminated by laser spot and twelve are partially illuminated; a uniform laser beam could be modeled without significant effect on the results. A more refined discretization should be used to make the Gaussian distribution  the latent melting heat must be considered in a more sophisticated to better adhere to the physic of the process; the dependence of the thermal conductivity from the temperature and its variation between powder and bulk material must be studied more deeply. The use of a different program, more suitable for thermomechanical combined analysis, could give more accurate results,  the method could be a tool to create a useful base of knowledge in terms of deformations and residual stresses of different materials (aluminum, titanium alloy, steel, etc.). References Ahmadi A., Moghaddam N.S., Haluk M.E., Karaca E., Mirzaeifar R., 2016. Finite Element Modeling of Selective Laser Melting 316L Stainless Steel Parts for Evaluating the Mechanical Properties. ASME 2016 11th International Manufacturing Science and Engineering Conference, Volume 2. Carter L.N., Martin C., Withers P.J., Attallah M.M., 2014. 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Computational Materials Science, 126, 360-372. Papadakis L., Loizou, A, Bremen, S, Risse J.and Schrage J., 2014. A computational reduction model for appraising effects in selective laser melting. Virtual and Physical Prototyping, 9(1), 17-25. meaningful but this would increase dramatically the analysis time. On the basis of the results some future improvement can be foreseen: