Changes in grain-boundary structure, due to the absorption of He atoms, were investigated theoretically and experimentally. The local intergranular dilatation in a plane layer of sub-atomic thickness was monitored. It was established that the dilatation was associated with a splitting of the cores of the grain-boundary dislocations, and with a decrease in the grain-boundary stacking-fault energy. Intergranular damage was related to changes, in the parameters of grain-boundary dislocations, that were caused by the absorption of He.

Changes in the Fine Structure of Grain Boundaries, Induced by the Absorption of Helium, and Helium Embrittlement. V.I.Gerasimenko, I.M.Mikhailovskii, I.M.Neklyudov, A.A.Parkhomenko, O.A.Velikodnaya: Technical Physics, 1998, 43[7], 803-8