| Abstract Scope |
As countries and private companies around the world have engaged in a new space race, not only to explore but also to use Space and colonize other cosmic objects like the Moon and Mars, manufacturing in space is no longer a distant dream but a pressing need. Therefore, materials joining in space has become a critical enabling technology for the rapidly growing in-space servicing, assembly, and manufacturing (ISAM) sector. Today, no metallurgical joining processes have been proven fit-for-service for execution in space. There is limited fundamental understanding of the effects of the space environment (gravity, atmosphere, and temperature) on the joining processes, the metallurgy, and performance of the joints. The current inability to effectively join materials in space significantly impairs the advancement of space exploration and economy. Our team, which also involves several members from the NASA MSFC, LRC, and GRC, investigates the impact of space conditions on the Laser Beam Welding (LBW) of metallic alloys. A 1 kW, 1070nm Yb-fiber pulsed laser was fitted into a vacuum chamber for microgravity experiments. To mimic space, our experimental setup rides aboard a parabolic flight where high-vacuum and variable gravity (from µg to 1.8g) experiments address the impact on weld geometry, microstructure, and defect formation on Al-Fe- and Ti-based alloys. This research represents a significant step toward qualifying LBW for ISAM applications and supports the broader goal of enabling autonomous, on-demand fabrication and repair in orbit and beyond. Finally, the insights gained from this work contribute to improving robust and predictive Integrated Computational Materials Engineering (ICME) frameworks and help establish design and process qualification standards for welding in space. |