Permeation behavior of tritium through F82H steel

The tritium permeation behavior through F82H steel from approximately pure tritiated water vapor diluted with He was investigated and the as-received and the permeation-experimented sample surfaces were analyzed by means of SEM, EDX and XRD. Extremely slow but obvious tritium permeation through F82H steel could be observed. It is indicated from the surface analyses that an oxide layer composed of magnetite and hematite is formed during the permeation experiments. The permeabilities estimated using the partial pressure of molecular tritium under the extreme assumption that the redox reaction among tritiated water vapor, magnetite and hematite with forming molecular tritium reaches equilibrium indicate that apparent tritium permeation using tritiated water vapor for the inlet side would be proceeded by molecular tritium generated by the redox reaction, although it is expected that actual tritium permeation would be derived from dissociated tritium atom indicated in transition state during the redox reaction. (C) 2011 Elsevier B.V. All rights reserved.