Irradiation induced microstructural changes in Zr-Excel alloy

Edge-on dislocation loop in anisotropic hcp zirconium thin foil

“…Ion irradiation enjoys several benefits over both neutron irradiation, and it has been proven to be an excellent tool to simulate the radiation damage process in Zr and its alloys [11,17]. However, the free surfaces relaxation effects on the physical behavior of dislocation loops in thin TEM foil during in-situ ion irradiation experiments needs to be identified.…”

“…Loop losses on the grain boundaries and both surfaces of Zr thin foils implies that in the case of thin foil irradiation, surface effects have to be taken into account when compared to the data with the bulk material irradiation [8,11]. In a recent study on in-situ radiation damage of Mo thin foil, it has been shown that due to surface loop loss effects, 7e10 nm large denuded zones are formed near top and bottom surfaces of TEM thin foil [41].…”

“…Extensive experimental studies have been carried out to investigate ion/neutron irradiation induced micro-structural changes in hcp Zr and its alloys, where the predominant irradiation damages are the 1=3〈1120〉 perfect dislocation loops of vacancy as well as interstitial nature [1,5,10,11]. At low irradiation doses, perfect atype dislocation loops of interstitial and of vacancy type with a 1=3〈1120〉 Burgers vector are formed, having the habit plane close to the prismatic crystallographic plane.…”

Effects of ion irradiation on microstructure and properties of zirconium alloys—A review

“…For irradiated M5 alloy, its critical dose at 573 K is 6.8 dpa [32]. For irradiated Zr-Excel alloy (Zr-3.5Sn-0.8Mo-0.8Nb), the value at 673 K is 2.5 dpa [39]. According to these studies, four points should be noted here to state the parameters influence Q10 on the nucleation and distribution of <c>-dislocation loops as follows:…”

“…The reason is that the Fe segregates from precipitates to matrix, the alloying element assists the nucleation of dislocation loops [41]. For the distribution around the grain boundary, the denuding of c-loops are observed in both 1 MeV Kr irradiated pure Zr up to 1 dpa at 773 K and Zr-Excel up to 10 dpa at 373 K. From the energy-dispersive X-ray spectroscopy line scan analysis, there exists a Fe depletion zone near the grain boundary [33,39]. For preexisting dislocations, they act as preferential sinks and increase the probability of defect clustering.…”