The self-diffusivity of 54Mn in icosahedral quasicrystals was investigated at 723 to 1022K. The concentration depth profiles of the radio-isotope were measured by using anion-beam sputter-sectioning technique. It was found that the temperature dependence of the self-diffusivity of Mn in Al72Pd20Mn8 icosahedral quasicrystals could be described by:
D(m2/s) = 1.1 x 10-10exp[-134.0(kJ/mol)/RT]
The self-diffusivity of Mn in Al60Pd25Mn15 icosahedral quasicrystals was some 2 orders of magnitude smaller:
D(m2/s) = 3.6 x 10-10exp[-109.4(kJ/mol)/RT]
The self-diffusivity of Mn in the quasicrystals was 3 to 4 orders of magnitude lower than that in crystalline Al.
H.Nakajima, J.Asai, K.Nonaka, I.Shinbo, A.P.Tsai, T.Masumoto: Philosophical Magazine Letters, 1993, 68[5], 315-20
Table 45
Interdiffusion Coefficients in the Al-Cu-Mg System
as a Function of Temperature and Pressure
Pressure (MPa) | Temperature (K) | DMgCuAl (m2/s) |
0.101 | 793 | -2.9 x 10-14 |
0.101 | 813 | 1.5 x 10-14 |
0.101 | 833 | 1.2 x 10-13 |
0.101 | 853 | 8.1 x 10-14 |
1000 | 793 | -3.8 x 10-15 |
1000 | 813 | -2.1 x 10-15 |
1000 | 853 | -6.0 x 10-16 |
1000 | 833 | 9.3 x 10-15 |
2000 | 793 | 4.0 x 10-16 |
2000 | 813 | 1.2 x 10-15 |
2000 | 833 | -4.0 x 10-16 |
2000 | 853 | -7.6 x 10-15 |
3000 | 813 | -1.1 x 10-16 |
3000 | 833 | -2.6 x 10-16 |
Table 46
Interdiffusion Coefficients in the Al-Cu-Mg System
as a Function of Temperature and Pressure
Pressure (MPa) | Temperature (K) | DCuMgAl (m2/s) |
0.101 | 793 | -1.4 x 10-15 |
0.101 | 813 | 4.6 x 10-14 |
0.101 | 833 | -1.4 x 10-14 |
continued
Table 46 (continued)
Interdiffusion Coefficients in the Al-Cu-Mg System
as a Function of Temperature and Pressure
Pressure (MPa) | Temperature (K) | DCuMgAl (m2/s) |
0.101 | 853 | 5.2 x 10-14 |
1000 | 793 | 2.9 x 10-13 |
1000 | 813 | 3.5 x 10-15 |
1000 | 833 | 3.0 x 10-15 |
1000 | 853 | -4.8 x 10-15 |
2000 | 793 | 1.0 x 10-17 |
2000 | 813 | 6.0 x 10-16 |
2000 | 833 | -1.4 x 10-15 |
2000 | 853 | -4.0 x 10-15 |
3000 | 813 | 2.7 x 10-16 |
3000 | 833 | -3.3 x 10-16 |
Table 47
Interdiffusion Coefficients in the Al-Cu-Mg System
as a Function of Temperature and Pressure
Pressure (MPa) | Temperature (K) | DMgMgAl (m2/s) |
0.101 | 793 | 2.7 x 10-13 |
0.101 | 813 | 3.7 x 10-13 |
0.101 | 833 | 5.6 x 10-13 |
0.101 | 853 | 1.1 x 10-12 |
1000 | 793 | 5.7 x 10-14 |
1000 | 813 | 8.0 x 10-14 |
1000 | 833 | 1.3 x 10-13 |
1000 | 853 | 2.5 x 10-13 |
2000 | 793 | 1.2 x 10-14 |
2000 | 813 | 1.7 x 10-14 |
2000 | 833 | 2.9 x 10-14 |
2000 | 853 | 5.6 x 10-14 |
3000 | 813 | 3.8 x 10-15 |
3000 | 833 | 6.6 x 10-15 |
3000 | 853 | 1.3 x 10-14 |
Table 48
Interdiffusion Coefficients in Al-Cu-Mg-Ag Alloys at 813K
Coefficient | Magnitude (m2/s) |
DCuCu | 2.94 x 10-13 |
DCuMg | 1.20 x 10-14 |
DCuAg | 2.50 x 10-14 |
DMgCu | 5.50 x 10-14 |
DMgMg | 4.17 x 10-13 |
DMgAg | 5.00 x 10-16 |
DAgCu | 1.86 x 10-13 |
DAgMg | 5.60 x 10-14 |
DAgAg | 3.40 x 10-13 |