The atomic diffusion of 59Fe in an icosahedral alloy was studied by using sectioning methods at temperatures ranging from 568 to 799C (tables 4 and 5). It was found that, to within the accuracy of the method used, the volume diffusivity could be described by the expression:

D (cm2/s) = 450 exp[-2.55(eV)/kT]

These Arrhenius parameter values were similar to those found for Fe diffusion in other Al-based intermetallic alloys, and were consistent with a vacancy-driven mechanism.

J.L.Joulaud, J.Bernardini, P.Gas, C.Bergman, J.M.Dubois, Y.Calvayrac, D.Gratias: Philosophical Magazine A, 1997, 75[5], 1287-97

Table 4

Grain-Boundary Diffusion of 59Fe in an Icosahedral Al-Cu-Fe Alloy

Table 5

Bulk Diffusion of 59Fe in an Icosahedral Al-Cu-Fe Alloy