Measuring mechanical properties
This study focused on the best print temperature and extruder settings. Thermoplastic pellets enter the top of the extruder and exit through the nozzle at the bottom as beads with high viscosity. Inside the extruder’s barrel, a screw is responsible for the downwards movement of the pellets.
However, the extruder configurations affect the mechanical properties of the printed object differently. Examples of these settings are: the temperature of the extruder, the diameter of the nozzle, layer time, number of rotations of the screw per minute (RPM) and torque (the force delivered unto the pellets in the barrel by the screw).
Central in this research was a large scale application, thus two larger nozzles (9 and 12mm) were used in the material test. These nozzle sizes provided beads from 18 to 22mm wide. Furthermore, printing temperature varied as well. RPM, torque and layer time however were kept stable.
The focus thus lay on settings concerning temperature of the E25 extruder, nozzle diameters and their influence on the mechanical properties of prints.