International Reactor Dosimetry File 2002 - IAEA Publications

8. RADIATION DAMAGE FILES AND
COMPUTER CODES
P.J. Griffin, L.R. Greenwood
Commonly used response functions can be usefully formatted so that
they may be readily interfaced with neutron spectra. Therefore, the IRDF-2002
library has included response functions for neutron displacement damage per
atom (dpa) for iron, silicon and GaAs to support this application. The following
sections detail the response functions and provide attribution for the derivation
of the response.
8.1. IRON dpa (LIGHT WATER REACTOR PRESSURE VESSEL
DAMAGE)
The ASTM standard E693 is the source for the iron dpa response [8.1].
Iron dpa (Fig. 8.1) is used in applications supporting pressure vessel surveillance
calculations, which are performed in compliance with the US Nuclear
Regulatory Commission requirements. The standard incorporates the ENDF/
B-VI cross-sections in the iron dpa exposure function and recommends the use
of the Norgett–Robinson–Torrens (NRT) displacement formalism. This
‘damage energy to displacement’ conversion procedure is consistent with the
10 4
10 3
Iron dpa cross-section
10 2
10 1
10 0
10 –1
10 –2
10 –10 10 –9 10 –8 10 –7 10 –6 10 –5 10 –4 10 –3 10 –2 10 –1 10 0 10 1
Neutron energy (MeV)
FIG. 8.1. ENDF/B-VI based iron displacement cross-section.
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