Investigation of spatial relationship between helium bubbles and dislocation loops in RAFM steel

The spatial relationship between helium bubbles and dislocation loops was observed in detail by TEM in RAFM steel irradiated with 100 keV helium ion to a fluence of 1 × 1021 He+ • m−2 at 723 K. Two families of dislocation loops were observed, with b = ± <010> and b = ± <100>, and habit planes of (010) and (100), respectively. The striking observation is that all of the loops were decorated with helium bubbles. Meanwhile, bubbles are determined to be located inside the loop plane through the investigation using different g-vectors under zone axes of [111], [001] and [011].