Innovation: Multiplexing Extrusion System (MExS): Multimaterial AM system for tailored hybrid composites
Award Category: Manufacturing: Equipment and Tooling Innovation, 2025 CAMX ACE Winner
Company: Oak Ridge National Laboratory (ORNL) & University of Maine Advanced Structures & Composites Center
Objective: MExS is a dual-extrusion, high-throughput system for additive manufacturing of complex, multi-material composite structures. It allows simultaneous or switchable deposition of dissimilar materials—such as neat polymers, fiber-reinforced composites, and thermoplastic foams—within the same bead.
Results: This enables in-bead structures like ductile shell/strong core, composite shell/foam core, and switchable material gradients, previously unachievable via AM. Built for large-scale and hybrid AM systems, MExS cuts cycle time, improves interlayer bonding, and reduces purge waste.
Impact: By tailoring mechanical performance within a single print pass, MExS makes high-strength, lightweight, and multifunctional parts viable for aerospace, defense, energy, and infrastructure sectors.
From the Experts: “You can switch material on the fly with minimal contamination, reducing waste. You can print multiple materials simultaneously–one inside and one out or two side by side–in a single bead. It gives you a lot of design flexibility to achieve macrostructures that weren’t possible before. You can combine very different property materials and get the best of both worlds.”~ Halil Tekinalp, R&D Staff, ORNL
“I am really excited about the potential for using this in the modular construction area that we’re currently working in. We’re doing follow-on housing prints from BioHome3D using the offsite prefab approach. There are material and design problems that need to be solved, and I think there’s an opportunity to use this technology to solve it.”~ Susan MacKay, Chief Materials Officer, UMaine Advanced Structures & Composites Center
