I-Corps: Translation Potential of Metal Viscous Thread Printing for Three-dimensional (3D) printing to Produce Metal Foams

This I-Corps project is based on the development of a low-cost manufacturing process for producing programmable metal foams using widely available desktop three-dimensional (3D) printers and commercial metal-polymer materials. Metal foams are broadly used in industrial, defense, and aerospace applications including heat exchangers, flame arrestors, catalyst media, acoustic dampers, bone implants, and radio frequency absorbers, among other uses. Existing production methods for porous metal components with controlled internal structure require specialized equipment, making it difficult to scale economically for low- and medium-volume manufacturing. This technology enables manufacturers to produce metal foams with programmable density using affordable equipment rather than specialized industrial metal additive manufacturing systems. This may reduce production costs, shorten development cycles, enable distributed manufacturing, and expand access to advanced metal materials. In addition, this may lower the barriers to manufacturing programmable porous metals, and shorten lead time and improve order quantities for custom metal foam. This I-Corps project utilizes experiential learning coupled with first-hand investigation of the industry ecosystem to assess the translation potential of an additive manufacturing process that intentionally harnesses viscous thread instability during fused filament fabrication to create stochastic metal foam architectures with spatially programmable density. Conventional metal additive manufacturing methods explicitly fabricate ordered lattices or require expensive powder-bed systems. This technology programs the physical instability of an extruded metal-polymer filament to generate porous metallic structures that retain their architecture after debinding and sintering. Previous research demonstrated fabrication of copper, bronze, and 17-4 stainless steel foams with programmed density gradients. The resulting structures exhibited six times fewer post-processing cracks than density-matched rectilinear lattices, more than tenfold greater specific toughness at low density, tunable thermal conductivity, and maintained electrical conductivity. This may provide an improvement in lead time and geometric inflexibility in metal foam production. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.