Elastic strain associated with irradiation-induced defects in self-ion irradiated tungsten

Elastic interactions play an important role in controlling irradiation damage evolution, but remain largely unexplored experimentally.  Using transmission electron microscopy (TEM) and high-resolution on-axis transmission Kikuchi diffraction (HR-TKD), researchers from Oxford Materials, Oxford Engineering and Canadian Nuclear Laboratories correlated the evolution of irradiation-induced damage structures and the associated lattice strains in self-ion irradiated pure tungsten.  

The TEM revealed different dislocation loop structures as a function of sample thickness, which suggests that the free surfaces limited the formation of extended defect structures that were found in thicker samples.  

The HR-TKD strain analysis showed the formation of crystallographically-orientated long-range strain fluctuations above 0.01 dpa and a decrease of total elastic energy above 0.1 dpa.

The full paper is available to read online through Scripta Materialia:  'Elastic strain associated with irradiation-induced defects in self-ion irradiated tungsten'.