  The interdiffusion coefficients are estimated either following the Wagner's
method expressed with respect to the composition (mol or atomic fraction)
normalized variable after considering the molar volume variation or the den
Broeder's method expressed with respect to the concentration (composition
divided by the molar volume) normalized variable. On the other hand, the
relations for estimation of the intrinsic diffusion coefficients of components
as established by van Loo and integrated diffusion coefficients in a phase with
narrow homogeneity range as established by Wagner are currently available with
respect to the composition normalized variable only. In this study, we have
first derived the relation proposed by den Broeder following the line of
treatment proposed by Wagner. Further, the relations for estimation of the
intrinsic diffusion coefficients of the components and integrated
interdiffusion coefficient are established with respect to the concentration
normalized variable, which were not available earlier. The veracity of these
methods is examined based on the estimation of data in Ni-Pd, Ni-Al and Cu-Sn
systems. Our analysis indicates that both the approaches are logically correct
and there is small difference in the estimated data in these systems although a
higher difference could be found in other systems. The integrated
interdiffusion coefficients with respect to the concentration (or concentration
normalized variable) can only be estimated considering the ideal molar volume
variation. This might be drawback in certain practical systems.

Applied Physics;Materials Science