16 Jun 2022
LZH scientists are also investigating the influence of gravity on laser beam welding processes designed for space applications.LASYS expo, taking place between 21-23 June in Stuttgart, Germany, Laser Zentrum Hannover (LZH) is to show some of its latest innovations from plant and system technology and developments in the field of lightweight construction.
Among other items, the LZH will present (on its booth in hall 4, stand A19) individual complete solutions for processes and systems from laser material processing using selected laser processing heads.
Another focus is on the potential of smart additive laser manufacturing. The LZH will also be demonstrating how “smart” agricultural technology of the future can work and will present a laser-based process for sustainable and herbicide-free weed control.
In two presentations, LZH scientists will discuss the latest developments in laser-based additive manufacturing with glass (Tuesday, June 21 at 11:30 a.m. and Wednesday, June 22 at 1:30 p.m.). Furthermore, the Wissenschaftliche Gesellschaft Lasertechnik (WLT) and its members as well as industry partners have put together an application-oriented lecture program on current trends in the field of laser material processing (click here for the program, in German).
LZH probes laser welding in space
LZH scientists are investigating the influence of gravity on laser beam welding processes. Experiments at the Einstein Elevator at Leibniz Universität Hannover (LUH) are expected to provide important new insights (see below).
To equip space stations, fully assembled assemblies currently have to be transported into space. This takes up cargo space and leads to high fuel costs. One solution to this problem could be laser beam welding, which could be used to join add-on parts or spare parts together directly on site. And instead of replacing entire assemblies, existing equipment could be flexibly expanded, modified, or repaired, say the LZH team.
Specifically, the LZH team is investigating the flow behavior for laser beam welding of similar and dissimilar joints made of aluminum alloys and steel materials. For dissimilar welds, the scientists also want to analyze the mixing behavior of the materials in the melt. Furthermore, the influence of the greatly reduced convection under microgravity on the molten pool and the resulting joints will be investigated
The Einstein Elevator of HITec – Hannover Institute of Technology is the further development of a classical drop tower, with which experiments can be carried out under reduced gravity and microgravity (corresponding approximately to weightlessness). The achievable microgravity is less than 10-6 g, the maximum experiment duration is 4 seconds. The value of microgravity achievable in the Einstein Elevator without vacuum is 10-4 g. This condition corresponds, for example, to the conditions on the International Space Station ISS.
Project µg welding
The project "The behavior of metallic melts during laser beam welding under microgravity" (µg welding) is funded by the Deutsche Forschungsgemeinschaft e. V. (DFG, German Research Foundation) under the reference KA 3952/13-1.