Revealing dynamic processes in laser powder bed fusion with in situ X-ray diffraction at PETRA III

Erwin Krohmer, Felix Schmeiser, Benjamin Wahlmann, Jan Rosigkeit, Gloria Graf, Petra Spörk-Erdely, Helmut Clemens, Peter Staron, Carolin Körner, Walter Reimers, Eckart Uhlmann

Publikation: Beitrag in FachzeitschriftArtikelForschungBegutachtung


The high flux combined with the high energy of the monochromatic synchrotron radiation available at modern synchrotron facilities offers vast possibilities for fundamental research on metal processing technologies. Especially in the case of laser powder bed fusion (LPBF), an additive manufacturing technology for the manufacturing of complex-shaped metallic parts, in situ methods are necessary to understand the highly dynamic thermal, mechanical, and metallurgical processes involved in the creation of the parts. At PETRA III, Deutsches Elektronen-Synchrotron, a customized LPBF system featuring all essential functions of an industrial LPBF system, is used for in situ X-ray diffraction research. Three use cases with different experimental setups and research questions are presented to demonstrate research opportunities. First, the influence of substrate pre-heating and a complex scan pattern on the strain and internal stress progression during the manufacturing of Inconel 625 parts is investigated. Second, a study on the nickel-base superalloy CMSX-4 reveals the formation and dissolution of γ′ precipitates depending on the scan pattern in different part locations. Third, phase transitions during melting and solidification of an intermetallic γ-TiAl based alloy are examined, and the advantages of using thin platelet-shaped specimens to resolve the phase components are discussed. The presented cases give an overview of in situ X-ray diffraction experiments at PETRA III for research on the LPBF technology and provide information on specific experimental procedures.

FachzeitschriftReview of scientific instruments
PublikationsstatusElektronische Veröffentlichung vor Drucklegung. - 10 Juni 2022

Bibliographische Notiz

Funding Information:
The LPBF system used for the described experiments was designed and built as a part of Project No. 317078200, which is funded by the Deutsche Forschungsgemeinschaft (DFG). The authors acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities at PETRA III. The beamline P07 (HEMS) is operated by Helmholtz-Zentrum Hereon. The authors would like to thank Norbert Schell for his assistance in using the beamline. Beamtime was allocated for Proposal No. I-20191411.

Publisher Copyright:
© 2022 Author(s).

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