90.60 Close of review Sep 3, 2019
ISO
ISO/TC 85/SC 5 Nuclear installations, processes and technologies
International Standard
27.120.30 Fissile materials and nuclear fuel technology
Published
ISO 15646:2014 describes a procedure for measuring the densification of UO2, (U,Gd)O2, and (U,Pu)O2 pellets, achieved by heat treatment under defined conditions.
The densification of fuel in power operation is an important design feature. Essentially, it is dependent on structural parameters such as pore size, spatial pore distribution, grain size, and in the case of (U,Gd)O2 and (U,Pu)O2, oxide phase structure. A thermal re-sintering test can be used to characterize the dimensional behaviour of the pellets under high temperature. The results of this test are used by the fuel designer to predict dimensional behaviour in the reactor, because thermal densification in the reactor is also dependent on these structural parameters, albeit in a differing manner in terms of quantity.
PUBLISHED
ISO 15646:2014
90.60
Close of review
Sep 3, 2019