High-throughput measurements of interdiffusivity matrices in face centered cubic Ni–Al–Mo alloys at 1273–1473 K

Based on 15 diffusion couples located in face centered cubic single-phase region of ternary Ni–Al–Mo system, high-throughput determination of composition-dependent interdiffusivity matrices at 1273, 1373, and 1473 K was performed by using the recently developed numerical inverse method. The determined main interdiffusivities over the investigated composition and temperature ranges are all positive, and( ilde D_{{ m{AlAl}}}^{{ m{Ni}}})is generally larger than( ilde D_{{ m{MoMo}}}^{{ m{Ni}}}). Moreover,( ilde D_{{ m{AlAl}}}^{{ m{Ni}}})generally increases with concentration of Al, while( ilde D_{{ m{MoMo}}}^{{ m{Ni}}})increases with concentrations of both Al and Mo. In contrast, the cross interdiffusivities can be either positive or negative. Average relative errors of( ilde D_{{ m{AlAl}}}^{{ m{Ni}}},; ilde D_{{ m{AlMo}}}^{{ m{Ni}}},; ilde D_{{ m{MoAl}}}^{{ m{Ni}}}), and( ilde D_{{ m{MoMo}}}^{{ m{Ni}}})were evaluated to be 2.4, 5.1, 16.1, and 1.7% using error propagation. Furthermore, our prediction of composition profiles and interdiffusion fluxes based on evaluated interdiffusivity matrices agrees quite well with measured data. Traditional Matano–Kirkaldy method was also applied to further verify the reliability of obtained interdiffusivities. Besides, three-dimensional planes of activation energies of main interdiffusivities were also evaluated using the Arrhenius equation.