Auger-Based 3D Printing of Stretchable Liquid Metal Paste Interconnects: A Brief Tutorial

Liquid metals, in combination with compliant substrates such as silicone, provide a versatile material system for creating stretchable electrical conductors. A variety of methods have been demonstrated for fabricating stretchable wires and electronic circuits using liquid metals, including stenciling, aerosol deposition, and extrusion-based printing. In this work, we present a brief tutorial describing modifications required to equip a commercial 3D printing gantry with the capability to print liquid metal paste materials. An auger-based print head is used to provide volumetric extrusion, improving print yield and quality compared to constant-pressure extrusion. In addition to required hardware and software modifications, a brief assessment of common print failure modes and mitigation strategies is provided.