A spanner has been produced in zero gravity using 3D-printing of metal powder in a first for additive manufacturing. Parts are being printed in space, on the International Space Station, but using polymer materials. Printing high-strength parts in zero gravity using metal powers presents unique challenges.
"We used a completely new technology to print a wrench for the first time under zero gravity in our latest parabolic flight campaign in March," says Jens Günster, project manager and head of BAM’s Ceramic Processing and Biomaterials division.
To additively manufacture metal parts, metallic powder is laid down on a bed and locally melted by laser to build the part layer by layer. But metallic powders pose a challenge in zero gravity because they are potentially flammable and explosive.
To enable the process to work in space, the research group has developed a method that enables processing of metallic powders under a protective gas atmosphere. A process gas--in this case nitrogen--is drawn through the powder layers to stabilize the powder bed in the absence of gravity.
The technology has been developed by Bundesanstalt für Materialforschung und-prüfung (BAM), a research institute of the German Federal Ministry for Economic Affairs and Energy. It has been tested in two parabolic flight campaigns in cooperation with Clausthal University of Technology and German aerospace center DLR’s Institute for Composite Structures and Adaptive Systems in Braunschweig.