PETRA III Science Seminar | Do dislocations evolve during metal 3D printing? - an in situ synchrotron X-ray diffraction study

by Manas Upadhyay (Ecole Polytechnique)

Tuesday 21 Nov 2023, 14:15 → 15:00 Europe/Berlin

Online

Steve Gaudez¹, Kouider Abdellah Abdesselam¹, Hakim Gharbi¹, Zoltan Hegedüs², Ulrich Lienert², Wolfgang Pantleon³, Manas Vijay Upadhyay^1,*  
1 Laboratoire de Mécanique des Solides (LMS), CNRS UMR 7649, Ecole Polytechnique, IP Paris, Palaiseau, France   
E-mail: manas.upadhyay@polytechnique.edu  
² Deutsches Elektronen-Synchrotron (DESY), Hamburg, Germany  
³ Department of Civil and Mechanical Engineering, Technical University of Denmark (DTU), Kongens Lyngby, Denmark  
 

ABSTRACT  
Dislocation structures are ubiquitous in any 3D printed alloy and they play a primary role in  
determining the mechanical response of an alloy. While it is understood that these structures form  
due to rapid solidification during 3D printing, there is no consensus on whether they evolve due to  
the subsequent solid-state thermal cycling that occurs with further addition of layers. In order to  
design alloy microstructures with desired mechanical responses, it is crucial to first answer this  
outstanding question. To that end, a novel experiment has been conducted by employing high  
resolution reciprocal space mapping, a synchrotron-based X-ray diffraction technique, in situ during  
3D printing of an austenitic stainless steel [1]. It reveals that dislocation structures formed during  
rapid solidification undergo significant evolution during subsequent solid-state thermal cycling, in  
particular during addition of the first few (up to 5) layers above the layer of interest.

KEY WORDS: Dislocations; Synchrotron diffraction; Solidification; Intrinsic heat treatment;  
Microstructure evolution; XRD

REFERENCES  
[1] S. Gaudez, K. A. Abdesselam, H. Gharbi, Z. Hegedüs, U. Lienert, W. Pantleon, M. V. Upadhyay,  
“High resolution reciprocal space mapping reveals dislocation structure evolution during 3D  
printing”, Additive Manufacturing 71 (2023) 103602. https://doi.org/10.1016/j.addma.2023.103602