Influence of oxygen in the production chain of Cu–Ti-based metallic glasses via laser powder bed fusion

ABSTRACT

Laser powder bed fusion of metals (PBF-LB/M) is advantageous for manufacturing bulk metallic glasses with size and geometrical freedom. However, the oxygen uptake along the production chain can negatively impact the generation of high-quality, amorphous parts. In this context, Cu–Ti-based alloys were gas-atomised and additively manufactured using commercial- (CP) and high-purity (HP) feedstocks. The oxygen absorption in each processing step was tracked and related to the amorphous phase formation and glass-forming ability (GFA) of alloys. Results show an increasing oxygen absorption, considerably influenced by the starting feedstock, especially for CP. In HP material, the most contribution is inherent from the powder oxygen content. Results reveal the lack of influence of the oxygen content in the GFA. TEM analysis of commercial powder and PBF-LB/M sample show uniform and featureless micrographs, displaying the absence of oxygen-induced nucleation. The present contribution enhances the qualification and economic processability of amorphous metals by PBF-LB/M.

KEYWORDS:

• Metallic glass
• gas-atomisation
• powder properties
• oxygen
• powder bed fusion laser beam (PBF-LB)
• Vitreloy 101

Acknowledgements

The authors would like to thank the technical assistance obtained from F. Peschel, S. Evers, S. Schmidt, M. Rickers, S. Geißler, C. Cyron, C. Mahnke, P. Meier and T. Grieb. We also appreciate the fruitful discussions with the industrial project support committee and highly acknowledge the material provision. The support from I. Okulov is also valued. This research was funded by the German Federal Ministry for Economic Affairs and Energy (BMWi) within the Promotion of Joint Industrial Research Programme (IGF) due to a decision of the German Bundestag. It was part of the research project 21227 N (LaSaM) by the Association for Research in Precision Mechanics, Optics and Medical Technology (F.O.M.) under the auspices of the German Federation of Industrial Research Association (AiF).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by AiF Projekt [grant number 21227 N].

Notes on contributors

Erika Soares Barreto

Erika Soares Barreto is a Research Engineer at the Leibniz-IWT. Her work focuses on powder production via gas atomization and additive manufacturing of glass-forming alloys.

Jan Wegner

Jan Wegner has a background in Mechanical Engineering and works at the Chair of Manufacturing Technology at the University of Duisburg-Essen, supporting the research on the additive manufacturing of bulk metallic glasses.

Maximilian Frey

Maximilian Frey is a PhD student at the Chair of Metallic Materials at the Saarland University. His research concentrates on the development of bulk metallic glasses.

Stefan Kleszczynski

Stefan Kleszczynski, Dr., is part of the Academic Council of the Chair of Production Engineering and Head of the Rapid Technology Center at the University of Duisburg-Essen.

Ralf Busch

Ralf Busch, Prof. Dr., is Chair Professor of Metallic Materials at the Saarland University. He works in particular in the field of bulk metallic glasses.

Volker Uhlenwinkel

Volker Uhlenwinkel, Dr., is the former Head of the Melt Atomization and Spray Forming group at the Leibniz-IWT. He focused his research on spray compaction, atomization techniques, and powder processability as in additive manufacturing.

Lutz Mädler

Lutz Mädler, Prof. Dr., is the Director of Process Engineering at the Leibniz-IWT and holds a professorship position in Production Engineering at the University of Bremen. His research interests involve, among others, spray processing for particulate materials and nanoparticle technology.

Nils Ellendt

Nils Ellendt, Dr., is Head of Disperse Phase Transition Processes at the Leibniz-IWT and member of the Particles and Process Engineering group at the University of Bremen. The focus of his research is mostly on droplet generation and the scaling to more complex atomization processes.