The diffusion of V was measured, at 6 temperatures (table 20), in alloys with various low Co contents. An enhancement of the diffusion was observed at all temperatures. The pre-exponential factors and activation energies were evaluated by means of the least-squares fitting of the experimental data to the Arrhenius equation, and it was found that the results could be described by expressions of the form:

0.00at%Co:      D (m2/s) = 3.59 x 10-5 exp[-309.07(kJ)/RT]

0.08at%Co:      D (m2/s) = 5.51 x 10-5 exp[-313.11(kJ)/RT]

0.12at%Co:      D (m2/s) = 5.23 x 10-5 exp[-311.47(kJ)/RT]

0.25at%Co:      D (m2/s) = 5.12 x 10-5 exp[-309.86(kJ)/RT]

0.92at%Co:      D (m2/s) = 4.34 x 10-5 exp[-304.98(kJ)/RT]

2.16at%Co:      D (m2/s) = 6.17 x 10-5 exp[-307.43(kJ)/RT]

From the resultant values of the enhancement factors, and published data on the diffusion of Co in pure V, the correlation factors for Co diffusion in V were calculated for various temperatures.

Vanadium Diffusion in V-Co Dilute Alloys V.Segel, J.Pelleg: Philosophical Magazine A, 1997, 76[6], 1203-14

Table 20

Diffusivity of V in V-Co Alloys