The influence of metallic particulate inclusions on the mechanical and thermal performance of 3D printable acrylonitrile-butadiene-styrene/thermoplastic polyurethane fused polymer blends

Abstract

Acrylonitrile butadiene styrene (ABS) shows exceptional mechanical behavior, however, the application of ABS for manufacturing thin parts has been limited because of its significantly lower melt fluidity. Thermoplastic polyurethane (TPU), on the other hand, has acceptable melt fluidity, but its mechanical performance is limited when compared to ABS. This paper combines these two polymers and incorporates elongated iron powder particulates as a reinforcing agent to manufacture a cost-effective yet performance-enhanced blended polymer filament for 3D printing. The melt-mixing approach was followed for blended polymer filament manufacturing. The thermal performance of the extruded filaments was evaluated using differential scanning calorimetry (DSC). The glass transition and melting temperatures were found to be slightly higher for the particulate-reinforced samples when compared to the control unreinforced ABS/TPU blend. This is attributable to the fact that the inclusions limit the mobility of the structure therefore it requires more energy to break down the molecular structure. The tensile strength of the filaments was obtained using a uniaxial tension experiment whereas the fracture toughness of the 3D printed parts was determined using the microindentation technique. The tensile strength and fracture toughness was found to be increasing with an increase in iron powder dosage by up to 5 %. The results reflect that appropriate dispersion of iron particulates is required to achieve the desired performance enhancement. Overall, the findings of this paper can potentially lead to various cost-effective and efficient means for performance enhancement in the manufacturing of 3D printable blended polymer composite filaments.