Primary Radiation Damage:
from nuclear reaction to point defects

Technical Meeting (F4-TM-43223), 1 - 4 October 2012, IAEA Headquarters, Vienna, Austria
is followed by CRP F44003 (2013-2017)


   The displacement cross section is a reference measure used to characterize and compare the radiation damage induced by neutrons and charged particles in crystalline materials. To evaluate the number of displaced atoms Norget, Torrens and Robinson proposed in 1975 a standard (the so-called NRT-dpa), which has been widely used from that time.
   Nowadays this formulation is recognized as suffering from some limitations: it is not applicable for compound materials, does not account for the recombination of atoms during the cascade evolution, cannot be directly validated and has no uncertainties/covarincies as evaluated cross sections usually have now.
   Upgrading of the dpa-standard means the inclusion of the results of the Molecular Dynamics (MD), Binary Collision Aproximation (BCA) or other simulations for primary radiation defects (PRD), i.e. Frankel pairs (FP) and Interstitial Clusters, which survive after relaxation of the Primary Knockout Atoms (PKA) cascade.
   The essential advantages of the upgraded dpa-standard will be:
- non-dependence on the energy distribution of incident neutrons - this means more correct inter-comparison of radiation damage in the different facilities on the basis of the accumulated dpa-fluence
- it also becomes more feasible for comparison of neutron and charged particles or ion induced damage
- empirical validation against frozen defects at cryogenic temperature (NRT-dpa can never be observed)
- prediction of damage in polyatomic materials and alloys (NRT treats dpa in compounds by mathematical weighting of separated elements)

Purpose of the Meeting

   To find ways to overcome the drawbacks of the NRT standard and benefit from the recent developments in primary radiation damage simulations, the Technical Meeting has the objectives to discuss:

   As an outcome of discussions the definition of objectives and participating organisations for a new Coordinated Research Project (CRP) on this topic are expected.

Specific issues to be addressed

TM Summary Report



Crocombette, Dudarev, Fukahori, Griffin, Inozemtsev, Kahler, Konobeev, Kwon, Mota, Nordlund, Pechenkin, Ryazanov, Simakov, Simakov, Simeone, Stoller, Vila

Illustrative Examples (pure Iron)

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