IMPURITY DIFFUSION OF IRON IN MOLYBDENUM.

The residual activity technique was employed to determine the impurity diffusion coefficients of Fe**5**9 in Mo in the temperature range of 1000 to 1350 degree C. The diffusion coefficient at 1350 degree C was 1. 2 multiplied by 10** minus **1**2 cm**2/sec, which was larger than the value for the impurity diffusion coefficient of Co in Mo obtained by Peart et al. , but smaller than any value for the impurity diffusion coefficient of Fe in refractory metals such as Nb, Ta and W at the corresponding temperature. It was found that the temperature dependence of Fe**5**9 diffusivity in Mo showed the Arrhenius relationship.