Electrochemical behavior and effect of heat treatment on morphology, crystalline structure of self-organized TiO2 nanotube arrays on Ti-6Al-7Nb for biomedical applications.
In the present work, we investigate the formation of self-organized titanium oxide nanotube layers by anodic oxidation on titanium alloy Ti-6Al-7Nb in electrolyte solution containing sulfuric acid and hydrofluoric acid. The anodized surface was characterized by micro-Raman, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray spectroscopy (EDS). The corrosion behavior of the treated and untreated samples was investigated through electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization studies in simulated body fluid (Hanks' solution). The investigations show that the native oxide on the sample is replaced by self-assembled nanoarray by anodization. FESEM of samples annealed at 450 to 800 °C show tubular morphology whereas those annealed at 850 °C show collapse of nanotubes. Electrochemical impedance data of the substrate and 10 V anodized samples were fitted with a two-time constant equivalent circuit and that of anodized samples (20, 30 V) with a three-time constant equivalent circuit.
Department of Chemistry, Anna University, Chennai, Tamilnadu, India; Surface Engineering Division, CSIR-National Aerospace Laboratories, P.O. Box: 1779, Old Airport Road, Bangalore, Karnataka, India.
L
L
Mohan
Surface Engineering Division, CSIR-National Aerospace Laboratories, P.O. Box: 1779, Old Airport Road, Bangalore, Karnataka, India. Electronic address: canandan@nal.res.in.
C
C
Anandan
Department of Chemistry, Anna University, Chennai, Tamilnadu, India. Electronic address: nrajendran@annauniv.edu.
N
N
Rajendran
D020811:Biomedical Technology / Q000379:methods*; D003460:Crystallization; D017097:Electric Impedance; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D006358:Hot Temperature; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D016062:Porosity; D013052:Spectrometry, X-Ray Emission; D013059:Spectrum Analysis, Raman; D014025:Titanium / Q000737:chemistry*; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction
D014867:Water; C070282:Ti-6Al-7Nb alloy; C009495:titanium dioxide; D014025:Titanium
Annealing; Anodic oxidation; Corrosion; EIS; TiO(2) nanotubes