On the fabrication of ZrCxNy from ZrO2 via two-step carbothermic reduction–nitridation. Issue 5 (May 2015)

• Record Type: Journal Article
• Authors: Harrison, R.; Rapaud, O.; Pradeilles, N.; Maître, A.; Lee, W.E.
• Is Part Of: Journal of the European Ceramic Society. Volume 35:Issue 5(2015:May)
• Page Start: 1413
• Page End: 1421
• Publication Date: 2015-05
• Subjects: Nuclear fuel -- Inert matrix fuel -- Carbonitride -- Carbothermal reduction -- Nitridation; 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.2014.11.005
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: Processing parameters of a two-step carbothermal reduction–nitridation of ZrO2 as a UO2 /PuO2 simulant to fabricate ZrN and ZrCx Ny were examined. Variables studied were reaction time, reaction temperature and starting powder composition. Higher temperatures, longer reaction times and higher initial amounts of carbon in the starting material lead to increased nitridation similar to previous work with uranium oxide but reaction rate decreases with time. SEM and TEM of the reacted powders reveal regions of ZrC with ledges indicative of crystal defects with small particles of ZrN growing on the ZrC bulk material suggesting a reaction that occurs via Zr transport to the reaction site either through mass diffusion or evaporation–condensation of Zr( g ) and with N2( g ) forming the nitride. Annealing experiments on these mixed phases show formation of a solid solution which is rapid compared to the nitridation, where there is little to no formation of a solid solution.