Biomedical Engineering Reference
In-Depth Information
TABLE 9.5
Piezovoltage Peak Value (mV) for Type A Sample under Three-Point Bending
Electrodes
Sample Type A
1-1
′
2-2
′
3-3
′
4-4
′
5-5
′
6-6
′
1
1.06
1.71
1.23
-0.49
-1.28
-0.94
2
3.27
4.33
1.78
-1.92
-3.94
-2.13
3
1.35
1.32
1.30
-1.35
-1.66
-0.77
4
0.81
2.65
2.47
-1.75
-1.87
-0.79
5
2.39
1.10
1.63
-2.10
-0.99
-1.57
TABLE 9.6
Piezovoltage Peak Value (mV) for Type A Sample under Four-Point Bending
Electrodes
Sample Type A
1-1
′
2-2
′
3-3
′
4-4
′
5-5
′
6-6
′
1
0.69
0.10
-0.28
0.43
-0.10
-0.17
2
0.72
0.19
-0.44
0.55
0
-0.31
3
0.40
0
0.56
-0.47
0.14
0
4
0.54
0
0.80
-0.42
0
0.32
5
0.76
-0.15
-0.15
-0.22
-0.20
-0.50
3
2.0
8-8´
3P
4P
7-7´
3P
4P
1.5
2
1.0
1
0.5
I
II
0.0
0
-0.5
-1
II
-1.0
I
-2
-1.5
-2.0
-3
0
2000
4000
6000
8000
10000
0
2000
4000
6000
8000
10000
Time (ms)
Time (ms)
(a) Electrode 8-8´
(b) Electrode 7-7´
FIGURE 9.18
Typical plots of piezovoltage versus time for type B sample. (I: results for three-point test;
II: results for four-point test).
Fu et al. [23] summarized their analysis and observations as follows:
1. The differences in the piezovoltage signs between the two groups of
electrodes 1-1′ ~ 3-3′ and 4-4′ ~ 6-6′ are due to the fact that normal
stress is distributed symmetrically and shear stress is distributed
antisymmetrically about the loading axis in the sample under
