Irradiation-Induced Voids and Bubbles

Evolution of defects in Ti6-4 under Ti2+ ion irradiation: Focus on radiation-induced precipitates

“…Therefore, in this "high temperature regime" the size and density of the defects are drastically dependent on the temperature. Furthermore, as said in §2, a coupling between the flux and the temperature to obtain a given microstructure is evidenced in the literature [15,19]. For the same ion irradiation temperature, lowering the flux should lead to a microstructure representative of a higher neutron irradiation temperature.…”

“…At low tem peratures vacancies are immobile, PDs are annihilated mainly in the cascades by mutual recombination. At low temperatures the diffusion and segregation processes are very low and the defects are mainly due to displacement cascades [15,33].…”

“…Spinodal decomposition can occur for large supersaturation. Local segrega tion in solutes can be enhanced by the inverse Kirkendall effect [15,36]. Because the diffusion of vacancies induces a solute flux in the opposite direction, solute elements that diffuse the most rapidly will be depleted at sinks (grain boundaries, dislocations, cavities and interfaces) and, on the contrary, slower diffusers will segregate at sinks.…”

“…The temper ature for ion irradiation should be chosen to produce irradiation damage in materials relevant to nuclear reactor cores. Mansur [19] and Was et al [15] proposed a formula to determine the shift in temperature to compensate for the damage-rate difference when ion beam irradiation is used for simulating neutron irradiation.…”

“…The ion irradiations avoids long and expensive irradiations in nuclear reactors, leading to radio-active samples that are thus not easy to prepare and analyze. However, the dose-rates and the in teractions between the particles and the material are known to be very different in the case of neutron or ion irradiations [15]. Therefore the aim of this study is to reproduce with heavy ion ir radiations what happens with neutrons (dislocation loops, pre cipitation) and to complete the few data available about heavy ion irradiations in the literature on Ti6-4 alloy with temperatures representative of irradiation temperatures in a reactor.…”