Impact of metal additives on particle emission profiles from a fused filament fabrication 3D printer

Use of three-dimensional (3D) printing in industrial and residential settings has grown exponentially with the development of less expensive equipment. However, understanding of particle emissions from these machines is limited, particularly when additives are integrated into the printable filament feedstocks. In this work, we assessed emissions from a fused filament fabrication (FFF) printer that used two common thermoplastics, acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA), and variants of these materials doped with metal additives PLA-copper (PLA-Cu) and ABS-tungsten (ABS-W), the latter of which has not been reported in literature until now. Experiments were performed inside a custom enclosure and emissions were monitored with a fast mobility particle sizer (FMPS). Mean particle emission rates were higher for ABS (2.06 × 107 #/cm3) than PLA (1.64 × 106 #/min). Feedstocks with metal additives were observed to have higher mean emission rates of 3.05 × 108 #/min for ABS-W and 4.43 × 105 #/min for PLA-Cu when printed at the same temperature as their respective neat thermoplastics. Median particle diameter by number concentration during printing was greatest for neat PLA (57.2 nm), with PLA-Cu (22.7 nm), ABS (29.7), and ABS-W (26.7) significantly lower. Our results demonstrate that polymer filaments containing metal additives have particle emissions rates an order of magnitude higher than neat polymers printed at the same temperature and emphasize the variability that can occur based on sampling methods and build parameters.