Welding Without Wires in Space: Ultrasonic Joining for Lightweight Structures

Image from LSU

The Research Advance

On September 23, 2025, it was announced that a team at LSU in collaboration with Louisiana Tech University and Southern University and A&M College received funding from NASA for in-space assembly and repair of space structures by ultrasonic welding of thermoplastic composites and vitrimers.

The aim is the production of lighter, stronger, and reconfigurable space components, reducing dependencies on fully fabricated Earth-launched modules.

Why Materials Science & Aerospace Mechanisms Intersect

Ultrasonic welding of composite space structures links materials science, regarding composite behavior, welding of dissimilar materials, and vitrimers, with the assembly, repair, modularity of the mechanical and structural systems. The ability to weld joints in space rather than using bolts or adhesives for aerospace mechanisms-such as deployable trusses, habitat modules, or structural supports-opens new design pathways that reduce weight and complexity. Such a bridge between material innovation and mechanical system design implies that aerospace engineers will have to consider how joining methods behave under vacuum, microgravity, and thermal cycling.

The design of aerospace mechanisms has to integrate not just final materials but also joining and repair mechanisms-if welding can be done in situ, then modular structures can evolve rather than being fixed at launch. Second, material behavior under ultrasonic welding in space requires new qualification regimes for composites, vitrimers, and hybrid materials used in structural or mechanism-bearing components. Third, the move to on-orbit assembly will mean that mechanical system design will increasingly assume that parts can be joined or modified in space, with implications for tolerances, actuation, alignment, and servicing strategies.