Interdiffusivities were deduced from compositional variations which were measured across Ni/Ni3Al diffusion couple interfaces by means of analytical electron microscopy and electron probe microanalysis (table 106). The former method was used to make measurements at lower temperatures, while the latter method was used at higher temperatures. The Boltzmann-Matano technique was used to determine interdiffusivities in the Ni-rich disordered phase and in the Ni3Al ordered phase. The present interdiffusivity values were compared with literature data. It was found that the present interdiffusivities were consistent with those predicted by a modified Darken's equation.

M.Watanabe, Z.Horita, T.Sano, M.Nemoto: Acta Metallurgica et Materialia, 1994, 42[10], 3389-96

Table 106

Interdiffusion Parameters for the Ni-Al System