Biomedical Engineering Reference
In-Depth Information
Table 9.5
Influence of particle size and filling rate on σ, E, ε, T
c
and T
f
Mean
particle
size (μm)
Specific
surface
area (cm
2
/g)
Filing rate
(mass %)
σ (MPa)
Е (MPa)
ε (%)
Т
c
(8С)
Т
f
(8С)
5
1132
10
1.85
65
280
20
2.60
85
260
30
5.50
115
210
40
10.00
151
160
50
17.50
190
100
87
3
15
755
10
1.10
55
277
20
2.00
74
263
30
4.50
100
230
40
9.00
132
183
50
17.0
165
130
91
3
25
453
10
0.80
50
275
20
1.80
68
264
30
4.00
90
225
40
7.20
120
200
50
15.0
150
157
95
8
35
323
10
0.80
48
272
20
1.60
60
270
30
3.50
80
252
40
6.20
100
120
50
15.50
130
180
95
9
becomes greater than 20-25
m, the critical parameters are sustained and
even improved compared with those of the initial ceramic sample. The
decrease in critical temperature and increase in transition width for
nanocomposites with a mean particle size of 5-10
μ
μ
m, are related to two
factors:
.
lower content of small, particle-sized fractions of the ceramic during the
orthorhombic phase
.
enhanced utilization of oxygen in the reactions of thermo-oxidation
destruction of the binder compared with the bigger fractions.
The critical temperature of transition into the SC state for nanocompo-
sites with ceramic of mean particle size 20-25
m and higher is elevated. This
can be explained [19, 23, 25] by the intercalation of macromolecule elements
of the binder into the interstitial layers of the ceramic grains, as noted
earlier.
μ
