A study of Re and Al diffusion in Ni

Alloy couples of Ni-1(wt.%)Re/Ni-4.8(wt.%)Re and Ni-x%Re/Ni-x%Re-5.3(wt.%)Al with x being 1, 2 and 3 were annealed at different temperatures to investigate the diffusion behavior of Re in Ni and the effect of Re on the diffusion behavior of Al in Ni. The composition profiles of these alloys were measured by electron probe microanalysis, and used to calculate the diffusion coefficients and activity energies of Re and Al. The results showed that the diffusion activation energy of Re in Ni was 412 kJ/mol and that of Al increased slightly from 230 kJ/mol to 256 kJ/mol with Re content being varied from 1% to 3% in Ni matrix.