TY - JOUR
T1 - Microstructure, mechanical properties and fretting corrosion behavior of micro-arc oxide coatings on biomedical Ti6Al4V alloy for modular hip implant
T2 - Effect of Na2SiO3/KOH electrolyte concentration
AU - Qin, Zhangyue
AU - Zhang, Yali
AU - Zhang, Xiaogang
AU - Jin, Zhongmin
N1 - Publisher Copyright:
© 2026 Elsevier B.V.
PY - 2026/4/1
Y1 - 2026/4/1
N2 - In this study, micro-arc oxidation (MAO) coatings were prepared on biomedical Ti6Al4V alloy using electrolytes with varying concentrations of KOH and Na2SiO3. Subsequently, based on the actual service conditions of the artificial hip joint head-neck interface, fretting corrosion experiments were performed. Effects of Na2SiO3/KOH concentrations on growth characteristics, microstructure, mechanical properties, and fretting corrosion behavior of the coatings were systematically investigated. The results indicated that KOH predominantly modulated the microstructure and properties of coatings by altering discharge behavior, whereas Na2SiO3 exerted its influence primarily through facilitating SiO2 formation. Elevated KOH concentrations decreased the breakdown voltage and promoted coating growth, but also increased porosity and surface roughness, leading to diminished mechanical properties. Moderate increases in Na2SiO3 concentration enhanced coating density and mechanical properties. However, excessive Na2SiO3 resulted in microcracking and irregular porosity, which degraded the performance of coatings. Following fretting corrosion, abrasive wear was identified as the principal damage mechanism for all coatings. Fatigue wear also contributed to the fretting damage mechanism at high KOH concentrations. Furthermore, excessive Na2SiO3 concentrations shifted dominant damage mechanisms to severe fatigue and three-body wear. Appropriately increasing Na2SiO3 improved both the wear and corrosion resistance of coatings. Notably, when the Na2SiO3/KOH concentration ratio was 2:1 (4 g/L: 2 g/L), the resulting coatings exhibited optimal fretting corrosion resistance, enhancing the fretting corrosion resistance of the Ti6Al4V alloy by approximately 4.5-fold. The results provide a reference for the surface protection and MAO coating design of biomedical titanium alloys.
AB - In this study, micro-arc oxidation (MAO) coatings were prepared on biomedical Ti6Al4V alloy using electrolytes with varying concentrations of KOH and Na2SiO3. Subsequently, based on the actual service conditions of the artificial hip joint head-neck interface, fretting corrosion experiments were performed. Effects of Na2SiO3/KOH concentrations on growth characteristics, microstructure, mechanical properties, and fretting corrosion behavior of the coatings were systematically investigated. The results indicated that KOH predominantly modulated the microstructure and properties of coatings by altering discharge behavior, whereas Na2SiO3 exerted its influence primarily through facilitating SiO2 formation. Elevated KOH concentrations decreased the breakdown voltage and promoted coating growth, but also increased porosity and surface roughness, leading to diminished mechanical properties. Moderate increases in Na2SiO3 concentration enhanced coating density and mechanical properties. However, excessive Na2SiO3 resulted in microcracking and irregular porosity, which degraded the performance of coatings. Following fretting corrosion, abrasive wear was identified as the principal damage mechanism for all coatings. Fatigue wear also contributed to the fretting damage mechanism at high KOH concentrations. Furthermore, excessive Na2SiO3 concentrations shifted dominant damage mechanisms to severe fatigue and three-body wear. Appropriately increasing Na2SiO3 improved both the wear and corrosion resistance of coatings. Notably, when the Na2SiO3/KOH concentration ratio was 2:1 (4 g/L: 2 g/L), the resulting coatings exhibited optimal fretting corrosion resistance, enhancing the fretting corrosion resistance of the Ti6Al4V alloy by approximately 4.5-fold. The results provide a reference for the surface protection and MAO coating design of biomedical titanium alloys.
KW - Electrolyte concentration
KW - Fretting corrosion
KW - Micro-arc oxidation
KW - Silicate alkaline electrolyte
KW - Ti6Al4V alloy
UR - https://www.scopus.com/pages/publications/105028090387
U2 - 10.1016/j.matchemphys.2026.132068
DO - 10.1016/j.matchemphys.2026.132068
M3 - 文章
AN - SCOPUS:105028090387
SN - 0254-0584
VL - 353
JO - Materials Chemistry and Physics
JF - Materials Chemistry and Physics
M1 - 132068
ER -