ASTROBEAT: Advancing cold-welding technology for in-situ spacecraft repairs

This paper presents an overview of ASTROBEAT, an innovative in-orbit mission to investigate cold-welding as a new method for repairing spacecraft hull damage caused by hypervelocity impacts. The experiment is a technology demonstrator, launched on November 5, 2024, aboard a SpaceX CRS mission, to test cold-welding under microgravity conditions on the International Space Station (ISS). The phenomenon, which involves the fusion of similar metals at ambient temperatures under high contact pressures, benefits from the space environment, where the absence of reoxidation facilitates atomic diffusion, enabling bonding at reduced forces. The ASTROBEAT experimental setup, housed within a 1 U cube Nanolab installed on an ISS rack, incorporates material test beds, a hull perforation repair device, and custom electronic and data acquisition systems. The core experiment involves preloaded springs delivering controlled forces to metal pairs (CuSn4 and Al-2024T) designed to simulate patch applications for spacecraft hull breaches. A pico-camera monitors the actuation process to ensure successful deployment, while electrical resistance measurements provide real-time data on the welding process. Functional testing and in-orbit operations showed that ASTROBEAT worked nominally. Post-flight, the payload will be recovered for further analysis. By demonstrating the feasibility of cold-welding for spacecraft repair, ASTROBEAT addresses a critical gap in standardized in-situ maintenance solutions, enhancing spacecraft safety and enabling long-term sustainability in space exploration.