The microtomography beamline ID19 at the European Synchrotron Radiation Facility (ESRF) provides an energy of up to 120 keV for high speed radiography, including the possibility to use a polychromatic beam with a wide energy bandwidth, while simultaneously achieving large beam cross sections of up to 50x15mm2. The beamline ID19 offers the unique opportunity to achieve very high spatial and temporal resolutions with an excellent signal-to-noise ratio, especially for in situ high speed radiography of laser beam processes, due to its beam characteristics and ideal local conditions. Using X-ray phase contrast, it is possible to observe processes in the vapor keyhole and melt pool at very high frame rates of 100,000 images per second or more for steel or aluminum. The accompanying images illustrate a test setup for in-situ radiography during laser beam welding and resulting images after image processing.
Figure 1: Experimental setup for in situ synchrotron radiography and exemplary results
The communication between customized laser machine tools and the beamline enables laser-safe operation and time-synchronous acquisition of additional process data and measurement signals with full flexibility for the use of a wide variety of laser beam sources and processes.
The following high speed videos illustrate the capabilities of the beamline using two examples:
Laser beam deep penetration welding of high alloy steel (100,000 frames/second, 1 mm sample thickness)
DOI: https://doi.org/10.1007/s40194-023-01581-9 
Laser beam deep penetration welding of copper (20,000 frames/second, 2 mm sample thickness)
DOI: https://doi.org/10.1016/j.ijmachtools.2024.104224
Video published in https://doi.org/10.1016/j.ijmachtools.2024.104224 (CC 4.0)