TESTING THE DEGREE OF INFLUENCE ON TENSILE STRENGTH OF 3D PRINTING PARAMETERS IN CARBON FIBER REINFORCED PETG

Several factors affect a 3D printed geometry's strength at the same time. The strength of the printed geometry depends on a number of factors, including the material, printing settings, geometry shape, and orientation. In this research the magnitude of influence from specific printing settings. defined by the slicer software on the tensile strength of 3D printed specimens was examined. The printer used was of the FFF (Fused Filament Fabrication) type. The composite material chosen for the test was a PETG (Polyethylene Terephthalate Glycol) strengthened with carbon-fiber NEEMA3D™ CARBON: PLUS. The material comprises 20% carbon fiber and 80% PETG polymer. The FFF 3D printer belongs to the closed type category with a large size, as a result of which it can print all the specimens simultaneously and with stable environmental conditions. More specifically, the printer is the CreatBotTM D600 Pro with dimensions 600mm × 600mm × 600mm. The Flow Rate, the Printing Speed and the Nozzle Temperature were the three parameters selected for the experiments, since all three of them affect the fluidity of the material, in other words its ability to pass easily and quickly through the interior of the printing nozzle. The change in the value of each parameter was divided into three symmetrical values, i.e. three levels. The variation in the Flow was: 85%, 100%, 115%, the Speed was: 25mm/s, 35mm/s, 45mm/s and the Temperature was: 235°C, 245°C, 255°C. The three parameters and the three value levels generate 27 different combinations. Using the Box-Behnken design, 15 out of the 27 specimens were fabricated and tested.