Microwave sintering of nuclear ceramics

International audienceMicrowave sintering is a promising technique to bring innovative microstructures, while reducing temperature, processing time and energy consumption. This process could be used to improve nuclear ceramics sintering efficiency, reduce economic costs and to potentially improve fuels features. This paper describes the development of an instrumented and automated microwave setup, qualified on fuel surrogates, which will allow reproducible and reliable comparison between microwave and conventional sintering of nuclear fuels. Finite elements modeling were used to design the setup and a hybrid heating technique with a specific sintering cell (nature and geometry of insulator and susceptor) in a multimode furnace has been chosen to obtain uniform and controlled heating of the specimens. This setup allows heating under Ar/4%-H2 with a specific partial pressure of oxygen. The results will be used to evaluate the feasibility of nuclear ceramics microwave sintering and to look at the future development of an industrial furnace