The diffusion of Al and Zr was investigated in the β-Zr(Al) phase at 1203 to 1323K by using single-phase diffusion couples of pure Zr against Zr–2.8wt%Al. The interdiffusion coefficients exhibited a small increase with increasing Al concentration, and obeyed a quadratic compositional relationship. The impurity diffusion coefficient of Al in β-Zr was determined by extrapolating interdiffusion coefficients to a limiting concentration of Al, and was found to exhibit a temperature dependence of the form:

D (m2/s) = 5.567 x 10-6exp[-220.08(kJ)/RT]

A.Laik, K.Bhanumurthy, G.B.Kale: Journal of Nuclear Materials, 2002, 305[2-3], 124-33