Ni and Ga diffusion in polycrystalline Ni3Ga

The volume and grain boundary (GB) diffusion of 63Ni and 67Ga radiotracers in polycrystals of Ni3Ga intermetallic was studied in the vicinity of the stoichiometric composition A3B (23.5–28.3 at.% Ga). Both volume and GB diffusivity was investigated in the temperature interval 773–1373 K by the residual activity method. The obtained Ga volume diffusivity increases with increasing Ga concentration xGa; the increasing tendency of Ni volume diffusivity with increasing xGa is pronounced at lower temperatures. GB diffusivity of both Ga and Ni in Ni3Ga are close one to another and—contrary to the diffusion behavior of components in Ni3Al—they do not show any significant dependence on xGa.