Multi jet Fusion and Selective Laser Sintering: a 3D printing technology comparison

This work aims to compare the two state of the art Powder Bed Fusion Technologies, mainly from the mechanical properties point of view. For making a good comparison of the two technologies five stages have been followed in this thesis. In the first stage, an adequate standard for the tensile test, and the specimen used had to be chosen. This stage is very important because the chosen standard can affect the values of some of the results, and by considering a standard which is not used by the other institutes or laboratories, the value of the work and results will decrease, since they cannot be compared to the results of the other works related to these technologies. In the second stage, the specimen had to be designed according to the standard. Nine different printing orientations had been chosen, and consequently, a specific name was given to each of the designed specimens for each of the printing orientation. The third stage consists of preparing the job in the HP Jet Fusion 4200 and the SLS 3d printer FORMIGA P 110 and finally printing the 45 specimens in 9 different orientations for each of the two technologies. After the cleaning process, the parts were ready for the tensile tests. In the fourth stage, all the specimens had to undergo a tensile test, and with the help of MATLAB and the Force-Elongation data received from the tensile testing machine, the final stress-strain curves were obtained. In the fifth and final stage, after reporting the values of each mechanical properties in the comparison bar charts, comparing the values and obtaining the final results were done with a lot of care and attention. It has to be mentioned that this work was a collaboration of the Fiat Chrysler Automobiles (FCA) Prototyping Center with Politecnico di Torino Integrated Additive Manufacturing (IAM@PoliTO) Center, and the parameters used in the production phase of the specimens, such as the mixed powder ratio, the printing speed, etc., were the ones used in the real industrial condition, and not necessarily the same as the parameters used by the manufacturers of the powders and the machines to obtain the datasheets of their products.