VALIDATION OF A FINITE ELEMENT MODEL FOR FUSED FILAMENT FABRICATION ADDITIVE MANUFACTURING

Fused filament fabrication (FFF) is a material extrusion additive manufacturing (AM) process that works well with thermoplastic polymers and is notably inexpensive compared to other AM processes, leading to its increasing popularity for industrial applications. Finite element analysis (FEA) is used to simulate the thermal histories involved in FFF. In this paper, several simulation cases of increasing complexity are presented, and both a thermocouple and an infrared thermal imaging system are used to validate the simulation results. First, a steady-state case is conducted and simulated to corroborate the two validation tools and to calibrate the thermal emissivity value and conductivity coefficient of the thermoplastic used for testing, in this case, acrylonitrile butadiene styrene (ABS). Next, the thermal camera is tested for its response time by comparing its frame rate to the resulting thermal images. Lastly, MSC Digimat-AM is used to simulate the FFF printing process. It was concluded that infrared thermal imaging is suitable for in-process thermal data collection during FFF printing, but with several limitations, such as low resolution, thermal radiation from the print bed due to the nozzle, and reflections of surroundings off the print bed. Thermocouples can act as aids to calibrate the thermal imaging but affect the cooling rate of the surrounding filament.