Differences in cascade damage formation between different metals was among the topics discussed at a workshop in 1998 entitled ‘Basic Aspects of Differ­ences in Irradiation Effects Between fcc, bcc, and hcp

Metals and Alloys.’124 The papers collected in that volume of the Journal of Nuclear Materials can be consulted to obtain the details on both damage pro­duction and damage evolution. A brief summary of the observed differences and similarities will be presented in this section. Although the development of alloy potentials is relatively recent, there have been a sufficient number of investigations to provide a com­parison of displacement cascade evolution in pure iron with that in three binary alloys, Fe-C, Fe-Cu, and Fe-Cr.125-138 The motivation for each of these binary systems is clear. Carbon must be added to iron to make steel, and as a small interstitial solute it could interact with and influence interstitial-type defects. Copper is of interest largely because it is a primary contributor to reactor pressure vessel embrittlement when it is present as an impurity in concentrations greater than about 0.05 atom% (Chapter 4.05, Radi­ation Damage of Reactor Pressure Vessel Steels). Steels containing 7-12 atom% chromium are the basis of a number of modern ferritic and ferritic- martensitic steels that are of interest to nuclear energy systems (see Klueh and Harries13 ).