TY - JOUR

T1 - Corrosion behaviour of electropolished magnesium materials

AU - Kloiber, Jessica

AU - Schultheiß, Ulrich

AU - Sotelo, Lamborghini

AU - Sarau, George

AU - Christiansen, Silke

AU - Gavras, Sarkis

AU - Hort, Norbert

AU - Hornberger, Helga

N1 - Funding Information: G.S. and S.C. were funded by the European Union within the research projects 4D+nanoSCOPE and LRI C10 and by the “Freistaat Bayern” and European Union within the project „Analytiktechnikum für Gesundheits- und Umweltforschung - AGEUM“, StMWi-43–6623-22/1/3. L.S. is directly funded by the European Union’s H2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement AIMed no.861138, 2020–2023. Funding Information: The authors gratefully thank Regensburg Centre of Biomedical Engineering (RCBE) for providing laboratory consumables. They also thank Prof. Dr. Ing. Ulf Noster for providing the laboratory and equipment for electropolishing and Dr. rer. nat. Brigit Striegl for supporting in chemical questions and in the evaluation of the Raman data. G.S. and S.C. were funded by the European Union within the research projects 4D+nanoSCOPE and LRI C10 and by the “Freistaat Bayern” and European Union within the project „Analytiktechnikum für Gesundheits- und Umweltforschung - AGEUM“, StMWi-43–6623-22/1/3. L.S. is directly funded by the European Union's H2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement AIMed no.861138, 2020–2023. Publisher Copyright: © 2024

PY - 2024/3/1

Y1 - 2024/3/1

N2 - Although magnesium and its alloys are promising candidates as biodegradable implant materials, the tendency for localised corrosion mechanism in physiological environment limit their biomedical application. Electropolishing is an attractive strategy for improving the corrosion behaviour of metals, but it is still largely unexplored in magnesium materials. In this study, the characterisation of electropolished surfaces of AM50 and pure magnesium was performed, focussing on their in vitro degradation behaviour in cell medium. Corrosion rates were evaluated using potentiodynamic polarisation. The surface morphology before and after the onset of corrosion was investigated by scanning electron microscopy and confocal laser scanning microscopy. The presented electropolishing process led to improved surface performances, observable by significantly lower corrosion rates (0.08 mm·year−1 in Dulbecco's modified Eagle's medium), lower arithmetical mean height (0.05 µm), lower water contact angle (25–35°) and lower micro hardness (35–50 HV 0.1) compared to mechanically and chemically treated surfaces. MgO/Mg(OH)2 could be detected on electropolished surfaces. The localised corrosion mode could be reduced, but not entirely prevented. Electropolishing shows great potential as post-treatment of magnesium-based components, but detailed tests of the long-term corrosion behaviour are an important area of future research.

AB - Although magnesium and its alloys are promising candidates as biodegradable implant materials, the tendency for localised corrosion mechanism in physiological environment limit their biomedical application. Electropolishing is an attractive strategy for improving the corrosion behaviour of metals, but it is still largely unexplored in magnesium materials. In this study, the characterisation of electropolished surfaces of AM50 and pure magnesium was performed, focussing on their in vitro degradation behaviour in cell medium. Corrosion rates were evaluated using potentiodynamic polarisation. The surface morphology before and after the onset of corrosion was investigated by scanning electron microscopy and confocal laser scanning microscopy. The presented electropolishing process led to improved surface performances, observable by significantly lower corrosion rates (0.08 mm·year−1 in Dulbecco's modified Eagle's medium), lower arithmetical mean height (0.05 µm), lower water contact angle (25–35°) and lower micro hardness (35–50 HV 0.1) compared to mechanically and chemically treated surfaces. MgO/Mg(OH)2 could be detected on electropolished surfaces. The localised corrosion mode could be reduced, but not entirely prevented. Electropolishing shows great potential as post-treatment of magnesium-based components, but detailed tests of the long-term corrosion behaviour are an important area of future research.

KW - Biomedical application

KW - Corrosion behaviour

KW - Electropolishing

KW - Magnesium alloy

KW - Pure magnesium

KW - Surface characterisation

KW - Engineering

UR - http://www.scopus.com/inward/record.url?scp=85181881571&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/0b587b8c-01cb-3ec3-8619-2eb4e79d3cae/

U2 - 10.1016/j.mtcomm.2023.107983

DO - 10.1016/j.mtcomm.2023.107983

M3 - Journal articles

AN - SCOPUS:85181881571

VL - 38

JO - Materials Today Communications

JF - Materials Today Communications

SN - 2352-4928

M1 - 107983

ER -