Tritium permeation through engineering components : JET bellows experimentFunded under: JRC-FUSAFE 5C
For the safe operation of large fusion experiments that will use large quantities of tritium, the amount of tritium permeation through engineering components must be known. Although permeation data exist for inconel and stainless steel, they have been obtained at relatively high pressures compared to the 0.1 Pa tritium partial pressure present in a machine such as JET, where surface effects rather than bulk diffusion may be predominant. Furthermore, it is often assumed that oxide layers acting as permeation barriers are present on such components. However, for effectiveness, such barriers must be intact and this may not necessarily be the case of engineering components where mechanical stresses can lead to oxide cracking. This paper describes, in detail, a tritium compatible experimental loop developed to obtain data on tritium permeation through engineering components typical of those used on large fusion devices that will operate with tritium. Experimental permeation rates through the bellows are presented and an interpretation of these data is attempted on the basis of a simple surface-limited tritium release model. Possible consequences on the JET safety case are discussed.
Bibliographic Reference: Paper presented: 17th Symposium on Fusion Technology, Roma (IT), September 14-18, 1992
Availability: Available from (1) as Paper EN 36996 ORA
Record Number: 199310938 / Last updated on: 1994-11-29
Original language: en
Available languages: en