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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original component was the replacement of the coolant in the form of water with ethylene glycol for better performance. Likewise, regarding the solution of the printing bed, it was decided to purchase and implement the solution by E3D - High Temperature Heated Bed, shown in Figure 1 (b), which goes beyond the established requirements and can reach a surface temperature of 200 ºC.

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Figure 1 - (a) E3D Tian aqua assembly; (b) E3D - High temperature heated bed assembly

For the ambient temperature parameter, it was decided to develop a set of three customized subsystems in order to meet the defined requirements. The first subsystem developed was the design and construction of an 800 × 800 × 750 mm enclosure that would contain the developed additive manufacturing equipment, as shown in Figure 2 (a). This equipment is based on an aluminium profile frame, which supports a layer of 15mm polystyrene foam for thermal insulation, and a final outer layer of 2 mm aluminium sheets. This enclosure also has a double window door made of two 2mm thick polycarbonate sheets with a 20 mm gap between them. The second subsystem is the implementation of a bang-bang controlled hot air heating system to regulate the interior temperature of the chamber. For the implementation of this system, a Parkside PHLG 2000 E4 heat gun with a power of 2000 watts was used to blow hot air into the chamber of the assembly shown in Figure 2 (b). To control the entry of air into the chamber, a solid-state relay controlled by on-off controller logic integrated into the printer main board unit system was used. The third subsystem implemented was an additional radiant heating system based on the solution proposed by John Gardner et al. (Gardner et al., 2016). This system consisted of the use of 6 halogen bulbs LUXTEK 220-240V-50W in 3 pairs, placed at the 3 corners of the building plate as shown in Figure 3. When in use, these lamps are lit continuously and oriented towards the printing part.