Comparing the performance of different extruders in the Robocasting of biopolymer-nanoparticle composites towards the fabrication of complex geometries of porous Tungsten Carbide

Abstract

Porous tungsten carbide (WC) is a material that combines a high strength to weight ratio and electroconductivity, which makes it a candidate for the creation of lightweight structures with the application as structural energy components, or SECs. However, machining complex geometries out of porous WC can be challenging and can lead to a significant waste of material. Here we present the use of robocasting to print geometries using paste featuring a biopolymer and tungsten oxide nanoparticles. Once printed, these geometries can be heat treated in an inert environment to derive porous WC. The benefit of using an additive manufacturing approach towards the production of porous WC is the possibility of producing complex geometric samples for industrial applications that cannot be created through traditional machining techniques. While the robocasting approach we reported before succeeded in producing WC samples, such a process led to the poor print quality of the desired geometries due to inconsistent extrusion flow rate throughout the printing process. The consistent flow generated by the new robocasting system proposed here has resulted in reduced layer irregularities, leading to the improved print quality of the WC precursor when compared to our previous approach. The production of consistent geometries will now allow for conclusive experimentation on the drying and carbonization processes and serves as a robust step forward to unlocking the potential of manufacturing porous WC SECs using robocasting.