Titanium tracer diffusion in grain boundaries of α-Ti, α2-Ti3Al, and γ-TiAl and in α2/γ interphase boundaries

First principles study of normal and fast diffusing metallic impurities in hcp titanium

“…50 ppm Fe, can greatly increase the diffusivity of normal diffusers, and reduce the apparent activation energy of diffusion [3,[27][28][29][30]. When these fast diffusers are present, the distinction between normal and fast diffusers remains, but the values of the diffusivities and activation energies for normal diffusers are significantly different from those of more pure material.…”

Essentials in diffusion behavior of nickel- and titanium-aluminides

“…10, Ti GB self-diffusion in pure a-Ti is plotted in comparison with Ti GB self-diffusion in a 2 -Ti 3 Al and gTiAl [51]. While Ti bulk self-diffusion in Ti 3 Al was found to be almost independent of the alloy composition [23], Ti GB diffusion in Ti 3 Al changes notably with the composition.…”

“…The decrease in Ti GB diffusivity P ¼ dD gb in Ti 3 Al with increasing Al content is accompanied by an increase in the activation enthalpy Q gb and Q gb reaches the lowest value at the stoichiometric composition and gradually increases with increasing Al content [51]. Here d is the GB width and D gb is the GB diffusion coefficient.…”

“…the creep behavior. Specially designed experiments on such two-phase materials are attractive since both bulk [20,23] and GB diffusion [51] in the constituting phases were already studied in detail.…”

“…An increase in the Al content from 25 to 35 at.% reduces Ti GB self-diffusion up to an order of magnitude. For comparison, Ti GB self-diffusion in g-TiAl is practically independent of the composition [51].…”