Investigation of Titanium Oxide Layer in Thermal-Electrochemical Anodizing of Ti6Al4V Alloy
In this paper the combination of thermal oxidation and
electrochemical anodizing processes is used to produce titanium
oxide layers. The response of titanium alloy Ti6Al4V to oxidation
processes at various temperatures and electrochemical anodizing in
various voltages are investigated. Scanning electron microscopy
(SEM); X-Ray Diffraction (XRD) and porosity determination have
been used to characterize the oxide layer thickness, surface
morphology, oxide layer-substrate adhesion and porosity. In the first
experiment, samples modified by thermal oxidation process then
followed by electrochemical anodizing. Second experiment consists
of surfaces modified by electrochemical anodizing process and then
followed by thermal oxidation. The first method shows better
properties than other one. In second experiment, Surfaces modified
were achieved by thicker and more adherent thick oxide layers on
titanium surface. The existence of an electrochemical anodized oxide
layer did not improve the adhesion of thermal oxide layer. The high
temperature, thermal formation of an oxide layer leads to a coarse
oxide grain morphology and a complete oxidative particle. In
addition, in high temperature oxidation porosity content is increased.
The oxide layer of thermal oxidation and electrochemical anodizing
processes; on Ti–6Al–4V substrate was covered with different
colored oxide layers.
 D.M. Brunette, P. Tengvall, M. Textor and P. Thomsen. Titanium in
medicine, Springer, Heidelberg (2001).
 R. Boyer, G. Welsch and E.W. Collings. Materials properties handbook:
titanium alloys, ASM International, Materials Park, OH (1994).
 M.J. Donachie. Titanium: a technical guide, ASM International,
Materials Park, OH (1989).
 J.L. Gilbert, C.A. Buckley and E.P. Lautenschlager, Titanium oxide film
fracture and repassivation: The effect of potential, pH and aeration. In:
S.A. Brown and J.E. Lemons, Editors, Medical applications of titanium
and its alloys: the material and biological issues, ASTM STP 1272,
ASTM, Philadelphia (1996), pp. 199-214.
 J. Komotori, B.J. Lee, H. Dong and P.A. Dearnley, Corrosion response
of surface engineered titanium alloys damaged by prior abrasion. Wear
88-98 (2001), pp. 1-11.
 F. Galliano, E. Galvanetto, S. Mischler and D. Landolt, Tribocorrosion
behavior of plasma nitrided Ti-6Al-4V alloy in neutral NaCl solution.
Surf Coat Technol 145 (2001), pp. 121-131.
 M. Long and H.J. Rack, Titanium alloys in total joint replacementÔÇöa
materials science perspective. Biomaterials 19 (1998), pp. 1621-1639.
 P. Kofstad. High temperature corrosion, Elsevier Applied Science, Essex