Visualizing Laser Welding in Real Time with X-Ray Video

On 10th November 2010 a new x-ray video facility was put into operation at the Institut für Strahlwerkzeuge (IFSW) of the University of Stuttgart. With this equipment it is possible to visualize laser processes in real time with x-ray video technology for the first time in Europe.

X-ray video sequences with a frame rate beyond 1000 fps were recorded for the first time on 23rd November 2010. A laser deep-penetration welding process in 6 mm thick Aluminum was recorded with 5000 fps at a resolution of 512 x 512 pixel. The recording time was more than one second. This is a world-wide unprecedented performance and will open up significant new insights into the fundamentals of laser material processing.

With this high-resolution view into the interior of the workpieces the researches at the IFSW will be able for the first time to investigate the shape and above all the highly dynamic changes and of the capillary and the movement of the surrounding melt which are created by the laser beam during welding. The knowledge gained in this way is important to understand and to overcome current limitations caused by instabilities such as splattering, pore formation or humping that occur for instance at high welding speeds.