How Fraunhofer ILT is transforming industrial processes with synchrotron radiation
Led by the Fraunhofer Institute for Laser Technology ILT and the RWTH Aachen University – Chair for Laser Technology, the interdisciplinary team "Laser Meets Synchrotron" at the German Electron Synchrotron (DESY) in Hamburg is researching fundamental scientific questions that give rise to industrial innovations. In addition to these partners, the consortium includes the Friedrich-Alexander-Universität Erlangen-Nürnberg, the University of Stuttgart, the Technische Universität Ilmenau, and the Vienna University of Technology.
Project Manager Christoph Spurk from RWTH Aachen University is coordinating the transportation and set-up of systems, lasers, and optical components and distributing the tasks to the research team of physicists, IT specialists, materials scientists and mechanical engineers. They rotate in three shifts 24/7 and carry out a total of 700 different experiments in seven days. Their experiments penetrate deep into industrial laser processes such as welding, drilling and cutting, and help them better understand material properties and behavior, and ultimately optimize processes. "With synchrotron radiation, we can visualize realistic laser processes in real time at DESY, observe vapor capillaries, melt movements or the formation of pores," explains Spurk.
Precision in real time: optimized laser processes for industry and research
The research results show that stress cracks can be significantly reduced by selectively adjusting the laser settings, porosity can be minimized and electrical conductivity increased. Vapor capillaries and melt movements, which often cause defects, have been visualized in high resolution for the first time, enabling the team to optimize welding processes for high-power batteries.
Since it has such outstanding brilliance and intensity, synchrotron radiation not only enables users to investigate at a resolution in the micro and even nanometer range, but also provides insights into the finest material structures and dynamic processes. Optical systems focus the laser radiation specifically on the materials; high-speed cameras, which achieve frame rates of up to 50,000 frames per second, are used for visualization. Spurk and his team are already working on a system that should reach 200,000 Hz in the near future. To visualize the phase contrast, the team uses scintillators that convert X-rays into visible light. If the contrast is still too low, the researchers add tungsten or tungsten carbide particles to the material. The particles can be seen as black dots in the images and provide information about the melting movement.
Many sectors – automotive, aviation, hydrogen technology or microelectronics – need to weld copper or aluminum joints, as well as metal and plastic ones, and to do so flawlessly. Only real-time visualization makes it possible to identify the smallest material defects, defects that would not be visible using conventional methods.
Fraunhofer Institute for Laser Technology ILT
