Additive manufacturing of duplex stainless steel by DED-LB/M and PBF-LB/M – process-material-property relationships
ISSN: 1355-2546
Article publication date: 3 July 2024
Issue publication date: 30 July 2024
Abstract
Purpose
Additive manufacturing (AM) of duplex stainless steels (DSS) is still challenging in terms of simultaneously generating structures with high build quality and adequate functional properties. This study aims to investigate comprehensive process-material-property relationships resulting from both laser-directed energy deposition (DED-LB/M) and laser powder bed fusion (PBF-LB/M) of DSS 1.4462 in as-built (AB) and subsequent heat-treated (HT) states.
Design/methodology/approach
Cuboid specimens made of DSS 1.4462 were generated using both AM processes. Porosity and microstructure analyses, magnetic-inductive ferrite and Vickers hardness measurements, tensile and Charpy impacts tests, fracture analysis, critical pitting corrosion temperature measurements and Huey tests were performed on specimens in the AB and HT states.
Findings
Correlations between the microstructural aspects and the resulting functional properties (mechanical properties and corrosion resistance) were demonstrated and compared. The mechanical properties of DED-LB/M specimens in both material conditions fulfilled the alloy specifications of 1.4462. Owing to the low ductility and toughness of PBF-LB/M specimens in the AB state, a post-process heat treatment was required to exceed the minimum alloy specification limits. Furthermore, the homogenization heat treatment significantly improved the corrosion resistance of DED- and PBF-processed 1.4462.
Originality/value
This study fulfills the need to investigate the complex relationships between process characteristics and the resulting material properties of additively manufactured DSS.
Keywords
Acknowledgements
This work was funded by Bayerische Forschungsstiftung through the project AZ-1465-20 “Laser Directed Energy Deposition with in-situ alloying for the production of components made of duplex stainless steels”. The authors would like to thank Christophe Deraed and SP ECT RO Analytical Instruments GmbH for providing the OES system SP ECT ROMAXx and Precitec KG for providing the DEDprocessing head YC52. Furthermore, the authors are very grateful to the iCAT 2023 conference committee for selecting and inviting them to publish this work as an extended version of the conference paper.
Citation
Maier, A., Rühr, M., Tangermann-Gerk, K., Stephan, M., Roth, S. and Schmidt, M. (2024), "Additive manufacturing of duplex stainless steel by DED-LB/M and PBF-LB/M – process-material-property relationships", Rapid Prototyping Journal, Vol. 30 No. 7, pp. 1348-1364. https://doi.org/10.1108/RPJ-02-2024-0099
Publisher
:Emerald Publishing Limited
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