Radiotracer experiments were performed on oriented Ag/Cu bicrystals in order to study the effect of the inter-phase boundary structure upon mass transport along the interfaces. The tracer diffusion of 110mAg was measured along (011) inter-phase boundaries in the [100] and [011¯] directions, and along (111) inter-phase boundaries in the [011¯] and [2¯11] directions, at temperatures ranging from 593 to 882K (tables 16 and 17). It was shown that, for the cube-on-cube orientation, the interfacial structure was reflected in the diffusion behavior. It was found that Ag diffusion along anisotropic misfit dislocation arrays in (011) inter-phase boundaries was anisotropic, and was fastest along channels of rapid diffusion. Scatter in the diffusion data for (011) inter-phase boundaries indicated that their structure, contrary to morphologically stable (111) interfaces, depended upon the thermal history of the specimens. This was attributed to micro-faceting of the morphologically unstable (011) inter-phase boundaries.
J.Sommer, T.Muschik, C.Herzig, W.Gust: Acta Materialia, 1996, 44[1], 327-34
Table 16
Diffusivity of 110mAg along Mutually Perpendicular
Directions in (111) Ag/Cu Interphase Boundaries
Direction |
Temperature (K) |
D (m2/s) |
sD (m3/s)
|
[011¯] |
881 |
2.38 x 10-16 |
2.76 x 10-20 |
[011¯] | 773 | 7.75 x 10-18 | 4.64 x 10-21 |
[011¯] | 720 | 1.00 x 10-18 | 1.32 x 10-21 |
[011¯] | 674 | 1.33 x 10-19 | 3.63 x 10-22 |
[011¯] | 593 | 1.81 x 10-21 | 4.93 x 10-23 |
[2¯11] | 881 | 2.38 x 10-16 | 3.01 x 10-20 |
[2¯11] | 773 | 7.75 x 10-18 | 2.17 x 10-21 |
[2¯11] | 673 | 1.27 x 10-19 | 1.47 x 10-21
|
Table 17
Diffusivity of 110mAg along Mutually Perpendicular
Directions in (011) Ag/Cu Interphase Boundaries
Direction |
Temperature (K) |
D (m2/s) |
sD (m3/s)
|
[100] |
882.5 |
2.49 x 10-16 |
2.99 x 10-20 |
[100] | 774 | 8.35 x 10-18 | 2.02 x 10-21 |
[100] | 773 | 7.75 x 10-18 | 4.96 x 10-21 |
[100] | 773 | 7.75 x 10-18 | 7.76 x 10-21 |
[100] | 723 | 1.14 x 10-18 | 7.68 x 10-22 |
[100] | 674 | 1.33 x 10-19 | 4.85 x 10-22 |
[011¯] | 881 | 2.38 x 10-16 | 3.01 x 10-20 |
[011¯] | 874 | 1.96 x 10-16 | 1.39 x 10-20 |
[011¯] | 823 | 4.22 x 10-17 | 6.67 x 10-21 |
[011¯] | 771.5 | 7.34 x 10-18 | 1.24 x 10-21 |
[011¯] | 741.5 | 2.38 x 10-18 | 5.08 x 10-22 |
[011¯] | 673 | 1.27 x 10-19 | 1.22 x 10-22
|