Environmental Engineering Reference
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determined γ CNT values in terms of the CNT [11] are firstly listed in table 5. A good
agreement between them is shown. Thus, the obtained γ CNT values in the CNT are not γ sl0 ( T m )
values, but γ sl ( D n , T n ) ones. γ sl ( D n , T n ) < γ sl0 ( T m ) could be partly induced by different structures
between nuclei and bulk crystals although it is difficult to determine the nucleus structure.
The above argument can be further supported by considering the correlation of the incoherent
interface energy between adjacent crystals or grain-boundary energy γ ss0 with γ sl0 ( T m ), which
may be explained in detail in Section 3.1.
Table 5. The model predictions in terms of Eq. (2.26)
and the corresponding experimental results calculated from the
CNT [11] with relevant parameters listed in table 1
D n / h
γ sl ( D n , T n )
γ CNT
θ n
(mJ/m 2 )
Co
248
234
0.187
11.0
Ni
283
255
0.185
11.6
Cu
200
177
0.174
12.0
Pd
211
209
0.182
10.8
Ag
137
126
0.184
11.2
Pt
243
240
0.181
11.2
Au
150
132
0.172
11.6
Pb
36
33
0.133
14.0
Mn
206
206
0.206
10.2
Fe
186
204
0.164
11.6
Hg
21
24
0.247
9.0
Al
110
93
0.14
12.0
Sn
62
55
0.208
12.0
Ga
61
54
0.25
10.8
Sb
109
101
0.15
12.6
Bi
45
54
0.166
9.6
Ge
201
181
0.184
11.0
Ref
11
Similarly, although γ sl0 ( T m ) of pure Si was reported to be 352±38 and 332 mJ/m 2 [39],
recent experiment has shown that γ CNT = 380 mJ/m 2 at θ = 0.21 [91]. Combining Eqs. (2.26-c)
and (2.27-c), the real γ sl0 ( T m ) value of pure Si should be 680 mJ/m 2 , which corresponds to
γ sl0 ( T m ) = 738 mJ/m 2 by Eq. (2.13) and γ TS = 672 mJ/m 2 by Eq. (2.14).
As shown in Ref. [39], the γ sl0 ( T e ) values of Solid Al-liquid Al-Cu, Solid Al-liquid Al-Si
and Solid Pb-liquid Pb-Sn systems are only a litter larger than the γ sl0 ( T m ) values of pure Al
and Pb where T e is eutectic temperature. However, γ sl0 ( T e ) of Solid Si-liquid Al-Si system is
much smaller than γ sl0 ( T m ) of pure Si. The possible reason can be explained as the following:
T e / T m for Al and Pb are about 0.90 and 0.76 while that for Si is 0.50. For the bulk crystals,
γ sl0 ( T e )/γ sl0 ( T m ) for Al and Pb are 0.97 and 0.92 while that for Si is 0.25 in terms of Eqs. (16-a)
and (16-c). Although it is inappropriate that Eqs. (2.26-a) and (2.26-c) for pure metals and
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