Corrosion fatigue behavior of electron beam melted iron in simulated body fluid

• Published in: Npj Materials degradation Vol. 6; no. 1; pp. 1 - 13
• Main Authors: Wackenrohr, Steffen, Torrent, Christof Johannes Jaime, Herbst, Sebastian, Nürnberger, Florian, Krooss, Philipp, Ebbert, Christoph, Voigt, Markus, Grundmeier, Guido, Niendorf, Thomas, Maier, Hans Jürgen
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group 08.03.2022; Nature Portfolio
• Subjects: Biocompatibility; Biodegradability; Biomedical materials; Body fluids; Corrosion; Corrosion fatigue; Corrosion prevention; Electron beam melting; Failure mechanisms; Fatigue strength; Heat treating; Hot rolling; Iron; Microstructure
• ISSN: 2397-2106; 2397-2106
• DOI: 10.1038/s41529-022-00226-4

Abstract Pure iron is very attractive as a biodegradable implant material due to its high biocompatibility. In combination with additive manufacturing, which facilitates great flexibility of the implant design, it is possible to selectively adjust the microstructure of the material in the process, thereby control the corrosion and fatigue behavior. In the present study, conventional hot-rolled (HR) pure iron is compared to pure iron manufactured by electron beam melting (EBM). The microstructure, the corrosion behavior and the fatigue properties were studied comprehensively. The investigated sample conditions showed significant differences in the microstructures that led to changes in corrosion and fatigue properties. The EBM iron showed significantly lower fatigue strength compared to the HR iron. These different fatigue responses were observed under purely mechanical loading as well as with superimposed corrosion influence and are summarized in a model that describes the underlying failure mechanisms.