The lattice self-diffusion of 59Fe was measured at temperatures ranging from 847 to 1503K (table 11) by using standard radio-tracer methods. It was found that, at temperatures below 1014K, the Arrhenius plot had a downward curvature. This was attributed to B2-type atomic ordering. Overall, the temperature dependence of the self-diffusion coefficient could be described by:

D (m2/s) = 3.2 x 10-5exp{-204(kJ/mol)[1 + 0.1S2]/RT}

where S was the long-range order parameter.

Z.Tôkei, J.Bernardini, P.Gas, D.L.Beke: Acta Materialia, 1997, 45[2], 541-6

 

 

 

Table 11

Bulk Diffusion of Fe in Fe3Al

 

 

Temperature (K)

 

D (m2/s)

 

 

1503

 

2.26 x 10-12

1365

5.24 x 10-13

1324

3.34 x 10-13

1276

1.96 x 10-13

1224

5.02 x 10-14

1106

7.64 x 10-15

1083

3.48 x 10-15

1079

3.25 x 10-15

1042

2.10 x 10-15

1021

1.54 x 10-15

1001

7.21 x 10-16

974

1.95 x 10-16

949

8.30 x 10-17

943

7.46 x 10-17

899

1.54 x 10-17

898

1.25 x 10-17

972

5.16 x 10-18

847

1.40 x 10-18