Biomedical Engineering Reference
In-Depth Information
TABLE 1.2
Comparison of Different Methods for HA Coating Preparation
Coating
Thickness
Method
Advantages
Disadvantages
References
High
temperature
deposition
techniques
Pulsed laser
deposition
<5
μ
m
Coating crystalline and
amorphous; dense or
porous; active atmosphere
conditions
Expensive, time-consuming,
multiphase coating including
α
-TCP,
β
-TCP, TTCP besides HA
and amorphous HA
(Koh et al. 2007; Bao et al. 2005; Arias
et al. 2003; Katto et al. 2002)
Hot isostatic
pressing
0.2-2.0 mm
Produces dense coatings
Cannot coat complex substrates;
high temperature required;
thermal expansion mismatch;
elastic property differences;
expensive
(Onoki and Hashida 2006; Fu,
Batchelor, and Khor 1998)
Thermal spraying
High deposition rates; can
obtain various coating
thickness and can be used
for complex substrate
shapes; low cost
High temperature induces
decomposition; rapid cooling
produces amorphous coatings
(Wang, Lu et al. 2007; Yan, Leng, and
Weng 2003; Gu, Khor, and Cheang
2003; Cheang and Khor 1995; Oguchi
et al. 1992; Lima et al. 2005; Khor et
al. 2003)
30-200
μ
m
Low
temperature
deposition
techniques
Electrophoretic
deposition
0.1-2.0 mm
Rapid deposition rates; can
coat complex substrates
Non-uniform thickness; impurity;
poor biological ixation to the
metal substrates
(Wei et al. 2001; Xiao and Liu 2006;
Ma, Liang et al. 2003; Stoch et al.
2001)
Biomimetic
coating
<30
μ
m
Low processing temperatures;
can form bonelike apatite;
can coat complex shapes; can
incorporate bone growth
stimulating factors
Time-consuming; requires
replenishment and a constant pH
of simulated body luid
(Reiner and Gotman 2009; Bharati,
Sinha, and Basu 2005; Barrere et al.
2001; Rigo et al. 2004)
Sputter coating
<3
μ
m
Uniform coating thickness on
lat substrates; dense coating
Ca/P ratio of the coating is higher
than that of synthetic HA if RF
magnetron sputtering is used;
expensive; time consuming;
producing amorphous coatings
(Pichugin et al. 2008; Ding 2003; Nelea
et al. 2003; Nieh, Jankowsk, and
Koike 2001; Cooley et al. 1992)
Sol-gel method
<1
μ
m
Low processing temperature;
can coat complex shapes, can
obtain very thin coatings;
higher purity and
homogeneity; low cost
Some processes require controlled
atmosphere and high sintering
temperature
(Haddow, James, and Van Noort 1999;
Ak Azem and Cakir 2009; Avés et al.
2009; Duran et al. 2004; Tkalcec et al.
2001; Montenero et al. 2000; Gross et
al. 1998; Kim et al. 2005)
Source:
Y. Yang et al.,
Biomaterials
, 26, 3, 327-337, 2005. With permission.
