The tracer diffusion of 44Ti was measured using sectioning techniques, in alloys with Al contents ranging from 25 to 35at%, at temperatures of between 1373 and 1126K. The self-diffusion coefficient was found to be lower than that for self-diffusion in pure -Ti, and increased only slightly as a function of the Al concentration. The stoichiometric composition did not exhibit any special diffusional behavior. Overall, the results could be described by the expression,

D (m2/s) = 2.44 x 105exp[-288.2(kJ/mol)/RT]

Interdiffusion of the 25 and 35at%Al compositions was also studied. The interdiffusion coefficient was deduced by using the Boltzmann-Matano technique. There was again only a slight temperature dependence of the coefficient. From these results, the diffusivity of Al was found to be described by,

D (m2/s) = 23.2 exp[-394.5(kJ/mol)/RT]

J.Rusing, C.Herzig: Intermetallics, 1996, 4[8], 647-57