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Additive manufacturing (AM) has various independent parameters that affect the mechanical properties and quality of the produced parts that are not linearly the function of each other. Process parameters in metal AM are very hard to control, analyse and optimise because they affect each other even though they can be independently changed. Changing process parameters in a wide range is not possible due to the formation of problems such as cracks, balling, unmelted powders, porosity and distortion. In this paper, a numerical model to predict the value of tensile strength of selective laser melting (SLM) Ti-6Al-4V parts and analyse the effect of process parameters on the results has been proposed. Taguchi L25 Design of Experiment (DOE) across 125 samples to create a comprehensive and general overview of influential parameters on the build process was investigated. Specifically, parameters included laser power, scan speed, hatch spacing, laser pattern angle and heat treatment (HT). To evaluate and analyse the build process according to established statistical variances, a minimum of five samples based on ASTM standard (for tensile test) were prepared. Heat treatment was added to the DOE to analyse the combined process and post-process effects. Results were compared (cross-validated) against existing values found in the literature and were found to effectively predict and explain the behaviour of tensile strength when changing process parameters. [ABSTRACT FROM AUTHOR]

This experimental study investigates the effects of process parameters for 3D printing polylactic acid (PLA) samples on both the mechanical properties obtained and the energy consumption in the fused deposition modelling (FDM) process. The explained experimental activities provide an in-depth evaluation of all the strategies adopted in different temperatures and scan speed strategies. The results, extracted in tensile strength, ultrasonic inspection (UT), and specific energy consumption (SEC), highlight the printing parameters that mainly affect the mechanical characteristics of the final workpieces and the energy consumption to find an appropriate energy-saving energy strategy for the PLA additive manufacturing process. The results indicate a more excellent uniformity of the molded material, reducing the printing time and total energy consumption at high speeds (V = 110 mm/s) and one level of temperature (T = 215 °C). A new efficiency index has been introduced to release guidelines to pursue the best setup compromise. [ABSTRACT FROM AUTHOR]