INTERSTITIAL MIGRATION IN IRON AT 220 K

A synopsis is given of recent attempts to clarify the nature of the prominent resistivity recovery stage at 220 K (Stage III) in irradiated high‐purity α‐iron and of the related magnetic and mechanical relaxation processes. With increasing irradiation dose the height of this stage increases linearly, and its position shifts to lower temperatures according to a second‐order reaction. In accord with other experimental results this is taken as evidence for free migration of an elementary point defect in iron at about 220 K. Since vacancy migration can be excluded on the basis of thermal‐equilibrium measurements, Stage III is attributed to interstitial migration. Suggestions for the interpretation of the Stage‐III relaxation phenomena are presented. Copyright © 1979 WILEY‐VCH Verlag GmbH & Co. KGaA