The Laser Zentrum Hannover e. V. (LZH) is investigating the influence of gravity on laser beam welding processes. To equip space stations, fully assembled components currently have to be transported into space. This takes up cargo space and leads to high fuel costs. Laser beam welding could be a solution to this problem: attachments or spare parts could be joined together directly on site. Many conditions in space are different to those on earth. Among other things, vacuum conditions, radiation, electrical and magnetic fields ensure that materials and processes behave differently. The Einstein Elevator at Leibniz Universität Hannover (LUH) will be used to investigate exactly how space conditions affect metallic molten baths. This drop-tower-like device can be used to conduct experiments under reduced gravity and microgravity (equivalent to near weightlessness).
Specifically, the flow behavior for laser beam welding of similar and dissimilar joints made of aluminum alloys and steel materials will be investigated. Other topics include the mixing behavior of the materials in the melt and the influence of the greatly reduced convection in microgravity on the molten pool and the resulting joints. The name of the project is "The behavior of metallic melts during laser beam welding under microgravity" (µg welding).
