Multifunctional Fused Deposition Modeled Acrylonitrile Butadiene Styrene-Based Structures With Embedded Conductive Channels

The applicability of additive manufacturing (AM) continues to expand because of research and development efforts in industrial, academic, and governmental institutions. The lure of additive manufacturing lies in the quick time-to-market and ability to produce parts and components with high degrees of topographical complexity empowered by the layer-by-layer production approach. One challenge that is attracting a significant amount of attention is improving the multi-functionality of additively manufactured parts, as enabling multi-functionality will result in transitioning AM to a broader application domain. The objective of this paper is to report novel developments that improve the functionality of polymer-based parts by adding electrical conductivity and fluid management to the existing load-bearing capabilities. A space structure was 3D-printed using acrylonitrile butadiene styrene (ABS) with embedded internal channels throughout the entire structure and then sealed using an acetone-diluted epoxy. The inner surfaces of the embedded channels of the sealed structure were then metallized using an electroless silver-coating process; these processes were found to be robust and independent of the inner diameter and length of the structure. The electromechanical performance of the structure was verified by applying mechanical loading while monitoring the change in electrical resistivity. The latter was found to remain nearly constant up to the point of ultimate mechanical failure. Finite element modeling was used to identify the areas of structural weaknesses and assist in elucidating the failure modes. The results were found to be in good agreement with the experimental data.