Pressureless Rapid Sintering of UO 2 Assisted by High‐frequency Induction Heating Process
2008; Wiley; Volume: 91; Issue: 10 Linguagem: Inglês
10.1111/j.1551-2916.2008.02615.x
ISSN1551-2916
AutoresJae Ho Yang, Yong‐Woon Kim, Jong Hun Kim, Dong‐Joo Kim, Ki Won Kang, Young Woo Rhee, Keon Sik Kim, Kun Woo Song,
Tópico(s)Advanced materials and composites
ResumoHeat generation of uranium dioxide (UO 2 ) powder and its pressureless rapid sintering behaviors have been studied using a high‐frequency induction heating apparatus. The porous graphite housing has been used to prevent heat loss and to preheat the uranium oxides, simultaneously. At an elevated temperature, UO 2 powder generated extra heat by itself. The synergism of individual heat generation between the graphite and UO 2 powder could effectively heat the UO 2 to the sintering temperature of 1700°C. Using this process, densification behavior of cylindrical and disk‐type UO 2 green pellets according to the heating rate and grain structure of sintered UO 2 pellets were investigated. Rapid sintering caused a large crack around the circumference of the sintered pellet. The formation of cracks could be avoided when the heating rate or sample dimension are properly reduced. A dense and crack‐free UO 2 pellet with a relative density of up to 96% was produced within 5 min of the process time. The induction heat sintering process can be a potential candidate for the rapid fabrication of ceramics and composites.
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