Dilatometric study of a co-converted (U, Am)O2 powder. Issue 7 (June 2016)

• Record Type: Journal Article
• Authors: Ramond, L.; Horlait, D.; Delahaye, T.; Jouan, G.; Gauthé, A.; Arab-Chapelet, B.; Picart, S.
• Is Part Of: Journal of the European Ceramic Society. Volume 36:Issue 7(2016:)
• Page Start: 1775
• Page End: 1782
• Publication Date: 2016-06
• Subjects: Actinides -- Co-conversion -- Sintering -- Microstructure -- Calcination; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2016.01.028
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: A possible option to reduce the radiotoxicity of nuclear waste is to transmute minor actinides and notably americium into lighter short-lived elements in fast neutron reactors of fourth generation. It consists in irradiating uranium–americium mixed-oxide compounds named AmBB (Americium-Bearing Blankets) and located at the reactor core periphery. Among the processes developed to fabricate AmBB, a chemical synthesis route was investigated. Dense samples were achieved using a simplified pelletizing-sintering process from oxalate co-converted powder. This work focuses on the identification and comprehension of the steps occurring during the sintering of these co-converted (U, Am)O2 powders. To discriminate the different phenomena observed by dilatometric measurements, different experimental techniques were performed. It allowed identifying that the sintering of the finest particles occurred in the [1000–1350 K] range while the elimination of porosity and sintering of (U, Am)O2 larger grains is realized in the [1400–1900 K] range with an apparent activation energy of 430 kJ.mol −1 .