Evidence of a temperature transition for denuded zone formation in nanocrystalline Fe under He irradiation

Radiation-Induced Helium Bubbles in Metals

“…In the preceding section, we overview He bubbles nucleation, growth and coarsening in the interior of grains. Interfaces, mainly GBs and heterophase interfaces (bi-metal interfaces), have attracted tremendous interests in the past decades [64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112]. Two reasons are responsible for the tremendous research interest of interfaces.…”

“…Series of complex factors, including intrinsic factors (matrix, GB misorientations [79,80], GB energies [80], etc.) and extrinsic factors (temperature [82], He concentration [64], etc. ), are supposed to exert a non-negligible effect on BDZs formation and evolution.…”

“…Many studies [82,83,84,85] are performed to unveil the dependence of radiation tolerance on grain size and explore the underlying mechanisms on both CG metals and NC metals. Due to their huge disparity in the ratio of GB area to total volume, CG metals and NC metals irradiated by He at the same condition deliver quite different bubble morphologies and distributions [82,83,84,85]. For He irradiation, the enhanced radiation tolerance in NC metals is usually manifested as small and low-density bubbles [82,83,84,85].…”

“…Due to their huge disparity in the ratio of GB area to total volume, CG metals and NC metals irradiated by He at the same condition deliver quite different bubble morphologies and distributions [82,83,84,85]. For He irradiation, the enhanced radiation tolerance in NC metals is usually manifested as small and low-density bubbles [82,83,84,85]. A representative example for He precipitation in NC Mo and CG Mo is shown in Figure 8 [83].…”

Response of solidification cellular structures in additively manufactured 316 stainless steel to heavy ion irradiation: anin situstudy

“…One major challenge is that the microstructure of metallic materials subjected to high-energy particle irradiation undergoes serious degradation, forming various types of defects, such as Frenkel pairs, dislocation loops, etc., which further undermine the mechanical properties of irradiated materials [12][13][14]. An effective way to mitigate irradiation-induced degradation in materials is to introduce high-density defect sinks [15], such as free surfaces [16], high angle grain boundaries [17,18], twin boundaries [19], and phase interfaces [20]. Recent ex situ proton and helium ion irradiation studies on AM 316 SS found that dense dislocations trapped inside solidification cellular structures tended to undergo recovery and recrystallization during radiation, and may serve as defect sinks, thus help alleviate void swelling and helium bubble formation [9,10].…”