Biomedical Engineering Reference
In-Depth Information
Ta b l e 3
.
18
(
Contd
)
HV
(MPa)
UTS
(MPa)
YS
(MPa)
EL
.
(%)
RA
(%)
Fatigue limit
(MPa)
Structure type
Ti-6Al-4V ELI
(annealed)
—
965 875 10-15 25-47 515
To improve mechanical strength of titanium implants,
α
+
β
titanium alloys have been developed (Tables 3.19-3.21, Fig. 3.4).
These titanium alloys have the greatest commercial potential and
are widely used as load-bearing orthopedic implants due to their
relatively good fatigue resistance and biological passivity [36].
Ta b l e 3
.
19
Ti-based biomaterials
No.
Chemical composition
Crystallographic structure
1 Cp Ti — grades 1, 2, 3, 4
α
α
+
β
2 Ti-6Al-4V ELI
α
+
β
3 Ti-6Al-4V
4 Ti-6Al-7Nb
α
+
β
5 Ti-5Al-2,5Fe
β
-rich,
α
+
β
6 Ti-5Al-3Mo-4Zr
α
+
β
α
+
β
7 Ti-15Sn-4Nb-2Ta-0.2Pd
α
+
β
8 Ti-15Zr-4Nb-2Ta-0.2Pd
9 Ti-13Nb-13Zr
mostly
β
β
10 Ti-12Mo-6Zr-2Fe
β
11 Ti-15Mo
β
12 Ti-16Nb-10Hf
β
13 Ti-15Mo-5Zr-3Al
β
14 Ti-15Mo-3Nb
β
15 Ti-35.3Nb-5.1Ta-7.1Zr
β
16 Ti-29Nb-13Ta-4.6Zr
Ta b l e 3
.
20
Mechanical properties of biomedical Ti-based alloys
Structure
type
Ti, grade 1 240 170 24 30 102.7
α
Ti, grade 2 345 275 20 30 102.7
α
Ti, grade 3 450 380 18 30 103.4
α
Ti, grade 4 550 485 15 25 104.1
α
Ti
-
6Al
-
4V ELI
860
−
965 795
−
875 10
−
15 25
−
47 101
−
110
α
+
β
Ti
-
6Al
-
4V (a)
895
−
930 825
−
869 6
−
10 20
−
25 110
−
114
α
+
β
Ti
-
6Al
-
7Nb
900
−
1050 880
−
950 8
−
15 25
−
45 114
R
m
[MPa]
R
e
[MPa]
A
[%]
Z
[%]
E
[GPa]
Composition
α
+
β
Ti-5Al-2.5Fe 1020
895
15
35
112
α
+
β
(
Contd
)
