Experimental investigation of helium migration in a face-centered cubic aluminum was reported. A pure aluminum with 0.15wt% of 10B was neutron-irradiated to obtain 1.2 x 1024/m3 helium atoms in the metal according to the reaction 10B + n → 7Li + 4He. The post-irradiated metal was observed in situ via transmission electron microscopy while the sample was heated to 470C with a hot stage holder. A helium-rich area was found in the vicinity of nanometric 10B segregates that were not solute in the aluminum. The helium-rich area was characterized as a polygonal faceted region. According to EELS measurements, this area was saturated with NHe = 3 x 1028/m3 helium atoms, which were (30–65)% of the atoms in the observed area. It was found that the helium-rich area expands due to helium migration. Electron beam diffraction revealed that the preferred orientation of the helium atoms’ migration was normal to plane (0¯22). The results were consistent with models for helium atoms migration between interstitial sites for a face-centered cubic metal.

Experimental Investigation of Helium Migration in an FCC Aluminum Matrix. B.Glam, D.Moreno, S.Eliezer, D.Eliezer: Journal of Nuclear Materials, 2009, 393[2], 230-4