Coarsening-densification transition temperature in sintering of uranium dioxide

The concept of coarsening-densification transition temperature (CDTT) has b een proposed to explain the experimental observations of the study of sinte ring undoped uranium dioxide and niobia-doped uranium dioxide powder compac ts in argon atmosphere in a laboratory tubular furnace. The general method for deducing CDTT for a given material under the prevailing conditions of s intering and the likely variables that influence the CDTT are described. Th ough the present work is specific in nature for uranium dioxide sintering i n argon atmosphere, the concept of CDTT is fairly general and must be appli cable to sintering of any material and has immense potential to offer advan tages in designing and/or optimizing the profile of a sintering furnace, in the diagnosis of the fault in the process conditions of sintering, and so on. The problems of viewing the effect of heating rate only in terms of den sification are brought out in the light of observing the undesirable phenom ena of coring and bloating and causes were identified and remedial measures suggested. (C) 2001 Elsevier Science B.V. All rights reserved.