The Effect of Printing Parameters on Electrical Conductivity and Mechanical Properties of PLA and ABS Based Carbon Composites in Additive Manufacturing of Upper Limb Prosthetics

Abstract

Additive manufacturing technologies are dynamically developing, strongly affecting almost all fields of industry and medicine. The appearance of electrically conductive polymers has had a great impact on the prototyping process of different electrical components in the case of upper limb prosthetic development. The widely used FFF 3D printing technology mainly uses PLA (polylactic acid) and ABS (acrylonitrile butadiene styrene) based composites, and despite their presence in the field, a detailed, critical characterization and comparison of them has not been performed yet. Our aim was to characterize two PLA and ABS based carbon composites in terms of electrical and mechanical behavior, and extend the observations with a structural and signal transfer analysis. The measurements were carried out by changing the different printing parameters, including layer resolution, printing orientation and infill density. To determine the mechanical properties, static and dynamic tests were conducted. The electrical characterization was done by measuring the resistance and signal transfer characteristics. Scanning electron microscopy was used for the structural analysis. The results proved that the printing parameters had a significant effect on the mechanical and electrical characteristics of both materials. As a major novelty, it was concluded that the ABS carbon composite has more favorable behavior in the case of additive manufacturing of electrical components of upper limb prosthetics, and they can be used as moving, rotating parts as well.

Detailed Thermal Characterization of Acrylonitrile Butadiene Styrene and Polylactic Acid Based Carbon Composites Used in Additive Manufacturing

“…If we compare the carbon filler mass of ESD-PLA samples determined by the two different methods, the results are relatively close to each other, which suggests an estimated carbon content of 8%-10%. These results nicely correlate with literature data about the significantly better conductivity of ESD-ABS samples over the ESD-PLA ones [33].…”

“…The mechanical and structural characteristics are well known. In addition, information on electrical conductivity have been revealed recently, as well as structural characteristics determined by scanning electron microscopy [ 23 , 33 ]. Despite the intense research work in the field, the detailed thermal characterisation of the materials has not been carried out before.…”

“…However, an alteration that would significantly affect the thermal behaviour of these compounds during and after 3D printing was not observed ( Figures S1–S4 and S6 ). The applied filler had a significant effect on the mechanical properties and the electrical conductivity of the PLA and ABS filaments [ 33 ]. Working with these ESD compounds is beneficial for the developers as the whole printing process of a biomedical sensor can be performed under the same circumstances and instrument settings.…”

3D printed bismuth oxide‐polylactic acid composites for radio‐mimetic computed tomography spine phantoms

“…The tensile test specimens were printed with the flat side down and the long axis aligned with the x‐axis of the build platform. This orientation results in the majority of the deposited beads of material aligned parallel to the applied load, which has been shown to maximize the mechanical strength of printed specimens 27‐32 . Solid cylindrical specimens were printed with 8 mm diameters and 10 mm lengths for micro‐CT analysis (Figure 1b,c).…”

Biodegradable Poly(Lactic Acid) Nanocomposites for Fused Deposition Modeling 3D Printing

“…Carbon-based additives can be incorporated into PLA to increase thermal/electrical conductivity and mechanical properties [ 73 ]. The most common carbon-based additives include carbon nanotubes (CNTs), multiwalled carbon nanotubes (MWCNTs), and graphene nanoplatelets (GNPs) [ 8 , 74 ].…”