Details
| Original language | English |
|---|---|
| Article number | 112745 |
| Journal | Corrosion science |
| Volume | 246 |
| Early online date | 27 Jan 2025 |
| Publication status | E-pub ahead of print - 27 Jan 2025 |
Abstract
Cochlear implants (CIs) have revolutionized the treatment of profound hearing loss, yet their long-term durability remains a challenge due to potential corrosion-induced degradation of the platinum electrodes of the CI. This study examines the corrosion behavior of platinum wires under accelerated test conditions, and compares the results with corrosion patterns observed in explanted CI electrodes from patients after almost 1 year and 26 years. Accelerated corrosion tests with frequencies from 1 to 5 kHz were validated as predictive tools for long-term performance, as the surface morphologies of stimulated platinum wires exhibit notable similarities to those of explanted electrodes. The as-drawn wires analyzed in this study exhibit up to 50 % more corrosion attack than annealed ones. Additionally, the impact of grain orientation on corrosion is examined by testing platinum single crystals with different electrochemical methods. For this purpose, single crystals with the orientation [111], [110] and [100] were analyzed. The research highlights the importance of annealing platinum and minimizing plastic deformation during electrode assembly to enhance electrode durability. Corrosion was found to primarily occur at grain boundaries, with grain orientation showing minimal influence. These findings suggest that engineering grain boundary characteristics could significantly improve the corrosion resistance of polycrystalline electrodes, offering a promising pathway to enhance the longevity of CIs.
Keywords
- Electrochemical impedance spectroscopy, Grain boundary, Grain orientation, Material degradation, Polarization measurement, Single crystals
ASJC Scopus subject areas
- Chemistry(all)
- General Chemistry
- Chemical Engineering(all)
- General Chemical Engineering
- Materials Science(all)
- General Materials Science
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In: Corrosion science, Vol. 246, 112745, 15.04.2025.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - The influence of microstructure on the corrosion behavior of platinum used for cochlea implant electrodes
AU - Blank, Tatiana
AU - Behrens, Sabine
AU - Lange, Elisabeth Franziska
AU - Klose, Christian
AU - Canadinc, Demircan
AU - Durisin, Martin
AU - Lenarz, Thomas
AU - Maier, Hans Jürgen
N1 - Publisher Copyright: © 2025 The Authors
PY - 2025/1/27
Y1 - 2025/1/27
N2 - Cochlear implants (CIs) have revolutionized the treatment of profound hearing loss, yet their long-term durability remains a challenge due to potential corrosion-induced degradation of the platinum electrodes of the CI. This study examines the corrosion behavior of platinum wires under accelerated test conditions, and compares the results with corrosion patterns observed in explanted CI electrodes from patients after almost 1 year and 26 years. Accelerated corrosion tests with frequencies from 1 to 5 kHz were validated as predictive tools for long-term performance, as the surface morphologies of stimulated platinum wires exhibit notable similarities to those of explanted electrodes. The as-drawn wires analyzed in this study exhibit up to 50 % more corrosion attack than annealed ones. Additionally, the impact of grain orientation on corrosion is examined by testing platinum single crystals with different electrochemical methods. For this purpose, single crystals with the orientation [111], [110] and [100] were analyzed. The research highlights the importance of annealing platinum and minimizing plastic deformation during electrode assembly to enhance electrode durability. Corrosion was found to primarily occur at grain boundaries, with grain orientation showing minimal influence. These findings suggest that engineering grain boundary characteristics could significantly improve the corrosion resistance of polycrystalline electrodes, offering a promising pathway to enhance the longevity of CIs.
AB - Cochlear implants (CIs) have revolutionized the treatment of profound hearing loss, yet their long-term durability remains a challenge due to potential corrosion-induced degradation of the platinum electrodes of the CI. This study examines the corrosion behavior of platinum wires under accelerated test conditions, and compares the results with corrosion patterns observed in explanted CI electrodes from patients after almost 1 year and 26 years. Accelerated corrosion tests with frequencies from 1 to 5 kHz were validated as predictive tools for long-term performance, as the surface morphologies of stimulated platinum wires exhibit notable similarities to those of explanted electrodes. The as-drawn wires analyzed in this study exhibit up to 50 % more corrosion attack than annealed ones. Additionally, the impact of grain orientation on corrosion is examined by testing platinum single crystals with different electrochemical methods. For this purpose, single crystals with the orientation [111], [110] and [100] were analyzed. The research highlights the importance of annealing platinum and minimizing plastic deformation during electrode assembly to enhance electrode durability. Corrosion was found to primarily occur at grain boundaries, with grain orientation showing minimal influence. These findings suggest that engineering grain boundary characteristics could significantly improve the corrosion resistance of polycrystalline electrodes, offering a promising pathway to enhance the longevity of CIs.
KW - Electrochemical impedance spectroscopy
KW - Grain boundary
KW - Grain orientation
KW - Material degradation
KW - Polarization measurement
KW - Single crystals
UR - http://www.scopus.com/inward/record.url?scp=85216362097&partnerID=8YFLogxK
U2 - 10.1016/j.corsci.2025.112745
DO - 10.1016/j.corsci.2025.112745
M3 - Article
AN - SCOPUS:85216362097
VL - 246
JO - Corrosion science
JF - Corrosion science
SN - 0010-938X
M1 - 112745
ER -