Gabriel Spartacus

Research interests

My research interestes articulate around metallic materials and fabrication process optimisation thanks to advanced characterization techinques, such as in-situ / in-operando monitoring. My previous work mostly focus on synchrotron X-ray characterizations (SAXS, anomalous SAXS, WAXS, Radiography, etc.), but also involved neutron scattering and microscopy (APT, SEM, TEM) studies.

My current research topics are:

• Monitoring and understanding of the microstructural evolution of metals during the Additive Manufactiring (AM) process of Electron Beam-Powder Bed Fusion (PBF-EB).
  • Participated in the development and implementation of a sample environment replicating the PBF-EB process while allowing synchrotron X-ray scattering and radiography measurement. See Minimelt publication.
  • Involved in a Vinnova project (2023 - 2025) for understanding of cracking mechanisms in Ni-based superalloys by in-situ SAXS/WAXS observations with GKN Aerospace.
• Optimizing the microstructure after Electron Beam Welding (EBW) of metals, by in-situ (using the Minimelt) and ex-situ experiments.
  • Studied steel to Al dissimilar joining by EBW with various welding parameters, and followed the melt pool kinetics and the phase transformation kinetics during the process by in-situ synchrotron X-ray measurements.
• Monitoring of the precipitation kinetics and phase transformations in various metallic alloys (especially steels) during their fabrication process (or simulated fabrication process).
  • In depth understanding of different Oxide Dispersion Strengthened (ODS) steel grades precipitation during their fabrication process, in order to optimize their properties.
  • Understanding of secondary phase precipitation on 15-5 PH, 17-4 PH and CrMoV steel grades, in collaboration with Tao Zhou.
• Interests in large scale facilities (synchrotron X-ray, neutron sources) state of the art measurement techniques and their development. See CeXS technical report series.

Other roles

• Coordination and design of the Experimental Hutch 2 of the Swidish Materials Science beamline (P21.2) of the PETRA III synchrotron, for the CeXS center. See more information on the dedicate CeXS webpage.
• XRD responsible for the Hultgren Laboratory unit, working with a Bruker D8 DISCOVER and Siemens D5000.

Teaching

• PhD and postdoc courses on synchrotron X-ray techniques and data analysis (Stress/strain measurement workshop, X-ray diffraction measurements, MATRAC course for practical synchrotron measurement, etc.).
• X-ray diffraction characterization for master students (MH2000).

Education

I have performed a master of engineering majoring on materials science at the IMT Mines Albi in France. I achieved my Ph.D. study in France at the French Atomic Energy Commission in partnership with the SIMaP laboratory at Grenoble University. My Ph.D. thesis focused on the fabrication process (involving powder metallurgy and high temperature thermal treatment) of Oxide Dispersion Strengthened (ODS) steels for Gen. IV nuclear power plants applications. I mainly performed in-situ small angle scattering measurements during high temperature heating, using X-ray (analyzing anomalous scattering) and neutron as well as X-ray diffraction, atom probe tomography and electron microscopy.