By using mass spectroscopy, the H permeability of Cu at 760C was found to be equal to 4.8 x 10-8cm2/s atm½, while the diffusivity was equal to 6.3 x 10-6cm2/s.

J.I.Zvezdin, J.I.Belyakov: Fiziko-Khimicheskaya Mekhanika Materialov, 1967, 3[3], 349-51