A study was made of the penetration of solid Ga penetration along Al grain boundaries. It was found that there were 2 different results of the interaction between Al and Ga. One was crack propagation along Al grain boundaries, and the other was Ga penetration (wedges) along special boundaries. The surface diffusivity of Ga on the oxide-free surfaces of the newly-created crack surfaces was estimated to be between 1.3 x 10-13 and 1.4 x 10-13m2/s.

Unusual Solid Gallium Penetration in Polycrystalline Aluminum. B.Bokstein, V.Ivanov, E.Kletskina, A.Petelin, S.Petelin: Solid State Phenomena, 2000, 72, 245-50