It was found that H was introduced by mechanical abrasion, and the process was here studied by means of thermal evolution spectroscopy. The results showed that the source of H was H2O in the environment. The H was introduced deeply into the sample, and the amount in question, at atmospheric pressure and near to the melting point, was about 2 orders of magnitude greater than the solubility limit of H in Al.

S.Hayashi: Japanese Journal of Applied Physics, 1996, 35[1-12A], 6191-9