September 8, 2021 /

X-ray imaging of laser materials processing at the German Electron Synchrotron

High-speed X-ray diagnostics provides insights into hidden phenomena in laser materials processing
[Picture: IFSW]

In fall 2020, the German Electron Synchrotron (DESY) in Hamburg provided one week of experimental time to the scientists of the Institut für Strahlwerkzeuge (IFSW) and the Lehrstuhl für Lasertechnik (LLT) in Aachen. 

The high-quality X-ray beam enabled sensational insights into the various laser material processing processes of welding, cutting and selective laser beam melting. The investigations with the monochrome X-ray beam are not limited to the distinction between the gaseous and the solid material, which results from the different densities. The different optical properties of the aggregate states lead to a phase contrast, which allows to identify the transitional locations between liquid and solid material. This allows to capture the dimensions of melt pools during welding and melt films during cutting within the material during the process. 

Two exemplary results of this investigation are now freely available via the DaRUS database of the University of Stuttgart and can be properly cited via the corresponding doi. The first video (https://doi.org/10.18419/darus-2078) shows the two different laser beam welding modes of heat-conduction welding and deep-penetration welding. The video presents heat-conduction welding as a stable process with low penetration depth but high weld quality, while deep-penetration welding results in high penetration depths but is associated with fluctuations of the keyhole and formation of pores. The second video (https://doi.org/10.18419/darus-1824) shows the process of laser fusion cutting. For the first time, the captured images allow the direct measurement of the thickness of the melt film during a laser beam cutting process. 

Another publication (https://doi.org/10.3390/met11050797) presents an analysis of such X-ray videos on the effect of evaporation of volatile alloying elements on the keyhole geometry during welding of aluminum alloys.

Watch the videos also on our YouTube channel at:
https://www.youtube.com/watch?v=_p0uvyWdUr0
https://www.youtube.com/watch?v=I4DK9O4exzg

Contact: Dr. Christian Hagenlocher


October 2021

September 2021

August 2021

July 2021

April 2021

March 2021

February 2021

October 2020

September 2020

May 2020

February 2020

November 2019

October 2019

September 2019

July 2019

June 2019

April 2019

March 2019

December 2018

November 2018

August 2018

May 2018

March 2018

December 2017

August 2017

April 2017

March 2017

January 2017

December 2016

November 2016

June 2016

April 2016

February 2016

January 2016

December 2015

September 2015

April 2015

March 2015

October 2014

April 2014

March 2014

February 2014

January 2014

December 2013

November 2013

October 2013

June 2013

March 2013

February 2013

January 2013

October 2012

September 2012

August 2012

July 2012

June 2012

March 2012

January 2012

To the top of the page