Applied Viscous Thread Instability for Manufacturing 3D Printed Foams.

Traditional foams are fabricated via stochastic chemical processes that yield homogeneous material properties. Foams can exhibit a wide range of material properties by varying process controls allowing them to be used in many industrial and commercial applications. Previously, additive manufacturing could only produce foam approximations in the form of traditional lattice infill. Our work employs viscous thread printing (VTP) on a fused filament fabrication (FFF) printer, exploiting the semi-viscous nature of extruded filament to coil producing a new type of printed foam. The use of 3D printing in this application allows for significant advantages: spatial control of extrusion allows for graded material properties and custom foam shapes on-the-fly.