Anodic Oxidation of Titanium for Biomedical Application
MOHAMAD ALI Selimin
1,a
, NOOR HAAFIZA Mohd Idrus
1,b
,
and HASAN ZUHUDI Abdullah
1,c *
1
Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Onn Malaysia,
86400 Parit Raja, Batu Pahat, Johor, Malaysia
a
hd120043@siswa.uthm.edu.my,
b
noor.haafiza@gmail.com,
c
hasan@uthm.edu.my
Keywords: Anodic oxidation, Titanium, Simulated Body Fluid, X-ray diffraction, Scanning Electron
Microscopy.
Abstract. Anodic oxidation is a chemical method which used to produce a bioactive layer (oxide)
of Titanium (Ti). The aim of this study is to evaluate the effect of anodic oxidation upon Ti foil in
acetic acid (C
2
H
4
O
2
). The anodic oxidation was performed by varying the applied voltage (10 – 200
V) and concentration of the electrolyte (0.5, 1.5 and 3.0 M of C
2
H
4
O
2
). After anodic oxidation, the
Ti specimens were soaked in simulated body fluid (SBF) to observe the precipitation of
hydroxyapatite (HAP). The Ti sample was characterized using X-ray diffraction (XRD) and
scanning electron microscopy (SEM) after anodic oxidation and SBF. The precipitation of apatite
after soaked in SBF was observed using SEM. From this study, the applied voltage range from 100
to 200 V at low and high concentration of acetic acid resulting in porous surface of anatase. The
arcing process occurred during the oxidation process which lead to the formation of anatase and
sites for HAP growth (nucleation site). The SBF result shows that the anodised Ti is suitable to be
applied in biomedical especially as implant.
Introduction
Titanium has used widely for biomedical application, especially as a hard tissue replacement
(orthopedic) as well as in cardiac and cardiovascular fields due to desirable properties such as
relatively low modulus, excellent mechanical properties, high corrosion resistance and
biocompatibility [1-3]. Most of the applications of titanium are based on the special surface
properties and catalytic properties. However, titanium cannot meet all of the clinical requirements.
Therefore, in order to improve the biological, chemical and mechanical properties of titanium, a
surface modification is often performed [4]. This biocompatibility titanium needed surface
modification to enhance the tissue compatibility and bonding between implant and bone called as
bioactive layer.
There are many types of surface modification techniques can be applied to titanium to produce
titanium dioxide layer (titania or TiO
2
) [4-6]. Basically, there are three types of polymorphs of
titania; anatase, rutile and bookite [7,8]. Anodic oxidation has recently proven useful for producing
a titania coating on a Ti substrate. It is a simple technique, and it works by connecting the Ti to the
anode and the applying a direct current through the electrolyte solution. Anodic oxidation also
allows controlling the formation of a protective oxide surface layer which is much thicker than that
formed naturally [9-12]. Fig. 1 shows the schematic diagram of the anodic oxidation apparatus
[4,9]. The formation of the apatite on the Ti surface can be done by using in vitro test, simulated
body fluid (SBF) and the recipe same as prepared by Kokubo et al. [13].
In the present study, an oxide layer was produced by anodizing the Ti substrate in electrolytes of
acetic acid. The applied voltage and concentration of electrolyte were varied to emphasize the effect
of the acetic acid in order to produce anatase formation on Ti specimen. The characterization of
each specimen was done by using X-ray diffraction (XRD) and scanning electron microscopy
(SEM). The apatite formation on the Ti surface was observed after soaking in simulated body fluid
(SBF) for six days.
Advanced Materials Research Vol. 1087 (2015) pp 81-85 Submitted: 27.05.2014
© (2015) Trans Tech Publications, Switzerland Revised: 27.07.2014
doi:10.4028/www.scientific.net/AMR.1087.81 Accepted: 13.08.2014
All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of TTP,
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