German institute seeks help from aerospace industry to develop technology to form thin metal parts - but size is limited
A laser process that could be used to form thin lightweight metal aerospace parts with hollow structures is undergoing trials.
Researchers at the Fraunhofer Institute for Laser Technology in Germany claim the tensile strength of the laser-formed parts is as good as forgings and better than castings. Together with its industrial partner, German machine tool maker Trumpf, the institute is seeking assistance from aerospace companies for further studies.
Known as the direct laser forming (DLF) process, it operates in a similar way to laser sintering. However, sintering cannot form parts as thin or as hollow as those formed by DLF. In both processes, a metal powder is laid down layer by layer and a laser melts the powder particles so they bond together. DLF does not need the post-forming treatments that laser sintering requires, providing parts with higher tensile strength, but like sintering it needs an inert argon atmosphere. Stefan Jansen, one of the Fraunhofer researchers at the institute's facility in Aachen, says: "We think it's a very good technology for aeronautics. This is a new development in laser processes. We hope to find some more [industrial] partners. Our next challenge is to solve problems with the limitations in the size of small parts. We can only produce parts 120 x 120mm [4.7 x 4.7in] at the moment."
ROB COPPINGER / LONDON
Source: Flight International
