The permeation rate of D through high-purity membranes was measured by using the gas-driven permeation technique. Time-dependent and steady-state D-flux data were analyzed, and the effective diffusivities of the samples were determined. By using multi-layer permeation theory, the effects of surface oxide were eliminated and the diffusion coefficients for bulk Be were determined. The diffusion parameters which were obtained were:

2N8-purity:     D(m2/s) = 6.7 x 10-9exp[-28.4(kJ/mol)/RT]

2N-purity:     D(m2/s) = 8.0 x 10-9exp[-35.1(kJ/mol)/RT]

E.Abramov, M.P.Riehm, D.A.Thompson, W.W.Smeltzer: Journal of Nuclear Materials, 1990, 175, 90-5