Variable Gravity Parabolic Flight Laser Welding for In-Space Welding Development

Laser welding is a technology with a high potential for in-space manufacturing due to its accuracy, repeatability, heat input control, and its wide use in autonomous manufacturing. This research explore the laser welding of 316L stainless steel, Aluminum 2219, and Ti-6Al-4V. The parabolic flight enabled welding under lunar, mars, and microgravity. A 1.5 kW pulsed laser system was integrated with a high-vacuum chamber and a sensor array. Porosity was characterized with computed tomography. The weld microstructure were characterized using, optical microscopy, SEM, and EBSD. Weld geometry and microstructure were consistent across gravity levels. This indicates that the rapid melting and solidification from pulsed laser welding suppressed the effect of gravity-driven fluid flow. Initial characterization revealed that reduced-gravity welds had smaller and more spherical pores. This work is part of a larger effort to support development of in-space welding technologies.