Interdiffusion in the β-NiAl homogeneity range was studied by using the diffusion couple technique at 1000 to 1200C. Intrinsic diffusivities at 1000C, for various compositions (figures 31 and 32), were measured by means of Kirkendall marker experiments. Variations of the molar volume, with composition and partial molar volume of the species, were calculated by using the lattice parameter and the vacancy concentration. Tracer diffusion coefficients of the species were calculated from the intrinsic diffusivities. The influence of the vacancy wind effect upon the calculated results was determined.
A.Paul, A.A.Kodentsov, F.J.J.van Loo: Journal of Alloys and Compounds, 2005, 403[1-2], 147-53
Table 169
Grain Boundary Diffusion of Ni in Ni3Al-Based Alloys
Alloy | Temperature (K) | D (m3/s) |
Ni-Al | 1273 | 1.2 x 10-20 |
Ni-Al | 1173 | 1.7 x 10-21 |
Ni-Al | 1073 | 3.8 x 10-22 |
Ni-Al | 973 | 1.0 x 10-22 |
Ni-Al-Hf | 1373 | 3.3 x 10-20 |
Ni-Al-Hf | 1323 | 1.6 x 10-20 |
Ni-Al-Hf | 1273 | 7.0 x 10-21 |
Ni-Al-Hf | 1223 | 2.2 x 10-21 |
Ni-Al-Hf | 1173 | 9.9 x 10-22 |
Ni-Al-Hf | 1123 | 4.0 x 10-22 |
Ni-Al-Hf | 1073 | 1.7 x 10-22 |
Ni-Al-Hf | 1023 | 4.3 x 10-23 |
continued
Table 169 (continued)
Grain Boundary Diffusion of Ni in Ni3Al-Based Alloys
Alloy | Temperature (K) | D (m3/s) |
Ni-Al-W | 1373 | 1.9 x 10-20 |
Ni-Al-W | 1323 | 1.1 x 10-20 |
Ni-Al-W | 1273 | 3.7 x 10-21 |
Ni-Al-W | 1223 | 1.8 x 10-21 |
Ni-Al-W | 1173 | 7.5 x 10-22 |
Ni-Al-W | 1123 | 2.3 x 10-22 |
Ni-Al-W | 1073 | 1.1 x 10-22 |
Ni-Al-W | 1023 | 2.9 x 10-23 |
Ni-Al-Co | 1273 | 1.2 x 10-20 |
Ni-Al-Co | 1223 | 5.5 x 10-21 |
Ni-Al-Co | 1173 | 2.6 x 10-21 |
Ni-Al-Co | 1123 | 1.2 x 10-21 |
Ni-Al-Co | 1073 | 2.9 x 10-22 |
Ni-Al-Co | 1023 | 1.8 x 10-22 |
Ni-Al-Cr | 1323 | 6.1 x 10-20 |
Ni-Al-Cr | 1273 | 2.6 x 10-20 |
Ni-Al-Cr | 1223 | 7.8 x 10-21 |
Ni-Al-Cr | 1173 | 3.1 x 10-21 |
Ni-Al-Cr | 1123 | 9.1 x 10-22 |
Ni-Al-Cr | 1073 | 1.6 x 10-22 |
Ni-Al-Cr | 1023 | 6.5 x 10-23 |