Biomedical Engineering Reference
In-Depth Information
better corrosion resistance than that with a small amount of
silica. Besides, the ceramic reinforced with titanium decreased the
corrosion rate of Ti.
Table 7.4
Vickers microhardness, mean values of corrosion current
densities, corrosion potentials and corrosion rate at Ringers
solution of Ti-ceramic nanocomposites and microcrystalline
titanium (grade 4)
i
C
[A/cm
2
]
E
C
[V]
C
R
[mm/year]
Materials
HV
1.31 × 10
-5
Microcrystalline titanium
250
-0.36
0.363
8.12 × 10
-7
Ti-3 wt% 45S5
500
-0.31
—
Ti-10 wt% 45S5
620
1.20 × 10
-7
-0.42
0.004
Ti-3 wt% SiO
2
550
1.91 × 10
-6
-0.37
0.055
4.60 × 10
-7
Ti-10 wt% SiO
2
670
-0.43
0.006
8.65 × 10
-7
Ti-3 wt% Al
2
O
3
600
-0.29
—
1.51 × 10
-6
Ti-10 wt% Al
2
O
3
700
-0.63
0.046
7.4
Ti-45S5 Bioglass Nanocomposites
Bioglass is a ceramic material that is characterized by some degree
of surface reactivity. These materials are specially selected chemical
composition, which allows the physiological environment selective
chemical reaction with certain ingredients of the bioglass. This leads
to a lasting bond with living tissue and biomaterial surface.
After 20 h of mechanical alloying process, the Ti-45S5 Bioglass
(3, 10 vol%) mixtures have transformed completely to an
amorphous phases without the formation of on other phase [24].
Nanocrystalline Ti-45S5 Bioglass composites were achieved by
annealing of the amorphous material. According to the Scherrer
method or XRD proiles, the average crystallite size of titanium-45S5
Bioglass nanocomposites mechanically alloyed and heat treated was
about 40 nm.
Combined with analysis of EDS, it can be conirmed that the Ti-
45S5 Bioglass nanocomposites mainly consist of titanium matrix
with nanoparticles of Si, P, Ca, and Na (Fig. 7.11).
