It was noted that pressurized water reactor vessel steels were embrittled by neutron irradiation. Among the solute atoms, copper played an important role in embrittlement and various Cu-rich defects were experimentally observed to form. Kinetic Monte Carlo studies of rigid lattices was used to investigate the evolution of the primary damage. Since the point defects created by the displacement cascades exhibited very different kinetics, their evolution was tracked in two steps. In a first step, their recombination in the cascade region and the formation of interstitial clusters using so-called object diffusion were studied. The parameters of this model, based upon molecular dynamics simulations or on first-principles calculations, were investigated via the subsequent evolution of the primary damage with a model based upon a vacancy jump mechanism. These simulations, which relied on an adapted embedded atom potential, revealed the formation of copper-rich defects. Some of the potential's predictions that played a key role in the model were checked by ab initio calculation. The defects obtained from these simulations, subsequent to the primary damage created by displacement cascades, exhibited similarities with the ones observed by atom probe. The influence of temperature and Cu content on the final damage was investigated.

Kinetic Monte Carlo Simulations of Cascades in Fe Alloys. C.Domain, C.S.Becquart, J.C.Van Duysen: Materials Research Society Symposium – Proceedings, 2001, 650, R3.25.1-6