Enhancing surface quality and corrosion resistance of LPBF nitinol alloy through electrochemical polishing
Matteo Tognazzo, Rachele Bertolini, Andrea Ghiotti, Stefania Bruschi
Abstract. The use of additively manufactured (AM) nickel-titanium (NiTi) alloys in biomedical applications is gaining increasing attention due to their unique properties, such as the shape memory effect (SME) and superelasticity (SE). Given the stringent requirements for surface quality and corrosion resistance in biomedical products, electrochemical polishing (EP) emerges as a promising surface finishing technique. However, to date, most research studies have focused on EP as a finishing method for conventionally fabricated NiTi parts, with process parameters optimized for wrought Nitinol components. This study aims to bridge this gap by determining the optimal EP time to improve the surface finish of AM martensitic NiTi cylinders and evaluating the impact of different process conditions on their corrosion resistance. The results indicate that increasing EP time enhances surface roughness up to a certain threshold, beyond which further improvement becomes inefficient. Similarly, corrosion resistance improves with smoother surfaces, but this effect also plateaus beyond a certain point.
Keywords
Nitinol, Additive Manufacturing, Electrochemical Polishing, Surface Finish
Published online 5/7/2025, 11 pages
Copyright © 2025 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Matteo Tognazzo, Rachele Bertolini, Andrea Ghiotti, Stefania Bruschi, Enhancing surface quality and corrosion resistance of LPBF nitinol alloy through electrochemical polishing, Materials Research Proceedings, Vol. 54, pp 2210-2220, 2025
DOI: https://doi.org/10.21741/9781644903599-238
The article was published as article 238 of the book Material Forming
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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