Calculating the composition-dependent diffusivity matrix along a diffusion path in ternary systems: Application to β-(Ni, Pt)Al

A numerical inverse analysis has been developed to extract the composition-dependent interdiffusion coefficients from a single diffusion couple in ternary systems. Its application to various diffusion couples at 1100 ring operatorC in β-(Ni, Pt)Al shows that in the composition domain investigated: • The direct interdiffusion coefficient image increases as the platinum content increases.• A concentration gradient of platinum has no influence on the diffusion of aluminium, and the corresponding coefficient image is zero.• The cross coefficient image is constant and very small except for a deep minimum at an aluminium content of 50 at.%.These results are briefly discussed in relation with diffusion mechanisms in β-(Ni, Pt)Al.