PSI - Issue 37

Tiago Domingues et al. / Procedia Structural Integrity 37 (2022) 847–856 Tiago Domingues et al./ Structural Integrity Procedia 00 (2019) 000 – 000

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Figure 4 - Motor cooling setup

3. Results The results obtained from the developed machine have been divided into two sections. In the first section, it will be accessed whether the changes made in terms of machine capacities have made it possible to achieve the parameters defined for printing high-performance plastics, namely the temperature of the extruder, the temperature of the heating bed and ambient temperature. Then, in the second section, parts were produced in both PEI and PEEK, in order to access the performance of the printer in terms of the quality of the produced parts. 3.1. Machine Capabilities To access that the machine capabilities new temperature requirements were achieved five parameters were accessed throw experimental testing. The first evaluated parameter was the maximum temperature that the extruder could reach. To test this setting, the hot end of the E3D Titan Aqua extruder was turned on continuously for 15 minutes, setting the temperature in the controller to the maximum value specified by the manufacturer of 500 ºC. During this test the temperature was monitored using the extruder PT100 sensor and from this test it was concluded that the equipment could reach and maintain the maximum specified temperature of 500 ºC. The second assessment was to confirm that the acquired heated bed was able to operate according to the defined requirements. As in the previous experiment, the acquired equipment was set at the maximum temperature specified by the manufacturer, 200 ºC, for 15 minutes. Then the E3D Standard 104NT thermistor built into the heat bed was used for the monitoring the temperature during the preformed test, which concluded that the acquired heated bed could reach the indicated temperature of 200 ºC, which meets the defined requirements. The environmental heating system was also tested to confirm its compliance with the defined requirements. For this, two test methodologies were followed to test the two heating mechanisms developed, namely the hot air blowing system and the radiation system. The first consisted of testing the bang-bang controlled hot air blowing system by itself and the second test consisted of using the radiation system together with the hot air blowing system. When performing these tests, three different temperatures were analyzed. As a first step, the ambient temperature was monitored using a thermistor suspended in a location in the middle of the height of the enclosure, 155 mm from the side panel and 110mm from the polycarbonate door. The temperature of the part surface was also monitored, for this purpose being printed 20 × 20 × 20 mm PEI calibration cube which was placed in the center of the build plate, with a thermocouple attached to the surface facing the door, positioned 12mm from the bottom and 15.5 mm from the right side, as shown in Figure 5 (a) and Figure 5 (b). Finally, the stepper motor surface temperature was