Fabrication in outer space presents significant obstacles, even though a number of the methods are similar to those employed on Earth. Techniques such as riveting, bolting, and welding are pertinent, with the latter being first attempted by Soviet astronauts more than fifty years ago. Recently, NASA has established a collaboration aimed at in-space welding, emphasizing the investigation of how diminished gravity and varying atmospheric conditions affect weld integrity.
The Soviets were pioneers in successful space welding, completing the first effective weld during the Soyuz-6 mission in 1969. Subsequently, NASA explored welding methodologies during tests on the Skylab space station in 1973 and, in 1984, achieved the first (and only) welding in the open vacuum of space during an EVA on the Salyut-7 mission. Currently, NASA is investigating fiber laser-based welding, as outlined in a collection of presentation materials. Initial testing has been conducted during parabolic flight operations since August 2024, with additional experiments planned for space.
In 1996, NASA teamed up with the E.O. Paton Welding Institute located in Kyiv, Ukraine, to engage in a project regarding in-space welding as part of the ISWE initiative, which aimed at testing on the Mir space station; however, unexpected challenges ultimately resulted in the project’s cancellation. More recently, the European Space Agency (ESA) has been executing experiments with in-space welding, revisiting the electron-beam welding (EBW) technique from the 1969 Soyuz-6 mission. EBW ensures reliable control over welds in the high-vacuum conditions characteristic of space.
This raises a critical question: why opt for laser beam welding (LBW) instead of EBW? While EBW has specific drawbacks concerning atmospheric circumstances and material compatibility, its main advantage is its reduced power requirements in comparison to LBW. As LBW experiments advance further into the cosmos, they might open new avenues for groundbreaking construction methodologies necessary for erecting structures and habitats not only in space but also on the surfaces of the Moon and Mars.
Image Source: Mamun_Sheikh / Shutterstock
