Diffusion processes inβ-Zr(Al) phase: a thermodynamic approach

The diffusion behaviour in theβ -Zr(Al) solid solution phase was investigated in the temperature range 1203-1323 K using a thermodynamic approach. The Boltzmann-Matano relation used for determining interdiffusion coefficients and the Darken’s equations used for evaluating the intrinsic diffusion coefficients from velocity of movement of markers in diffusion couples were modified suitably. The composition dependent thermodynamic interdiffusion coefficients were evaluated using chemical potential gradient. Composition and temperature dependence of the thermodynamic interdiffusion coefficients were also established. The thermodynamic intrinsic diffusion coefficients of Al and Zr and their temperature dependence were determined using the modified Darken’s equations.