Characterization of particle emission from thermoplastic additive manufacturing

Particle emission from fused-deposition modelling (FDM) desktop 3D printer has raised concerns regarding indoor personal health due to the increased accessibility of printers. This study characterises the size, number and morphology of the emitted particles to understand particle formation processes and propose guidelines for their abatement. The effects of extruder temperature, layer height, filament colour and shape of printing object on particle characteristics emitted from a desktop 3D printer have been investigated. For first time, a novel thermogravimetric analysis (TGA) method is developed to emulate printing process, which offers an insight into particle formation during extruder heating, standing-by and during the printing process. Printing temperature and printing layer height demonstrate a major effect on the ultra-fine particles (UFP) emitted, while ABS filament colour shows a minor effect on the nanoparticle emissions. Local temperature and concentration of volatile organic material emitted from the filament play an important role on the number of particles formed, while printing duration and air change rate (ACH) affect particle size, morphology and emission rate. The results provide guidelines to develop printing settings that will lead to lower UFP emissions for improved indoor air quality. The developed TGA method demonstrates the qualitative behaviour of particle emissions from a material under heating, which is approximately proportional to an FDM printers' particle emissions; facilitating increased repeatability, time and cost efficiency for printing material assessment.