Spark plasma sintering of diamond-reinforced uranium dioxide composite fuel pellets

Abstract

2016-12-23T18:44:59

Raman spectroscopic investigation of graphitization of diamond during spark plasma sintering of UO2-diamond composite nuclear fuel

“…The mixture was dried in an oven at around 40 o C for one hour [13]. Under current mixing/milling condition, a uniform distribution of diamond particles can be obtained [3]. The powder was placed in a graphite die and sintered using a Dr. Sinter…”

“…Many materials such as silicon carbide (SiC) [1], carbon nanotubes (CNT) [2] and diamond [3] have been investigated and high density composite pellets have been successfully fabricated utilizing a new sintering technique called spark plasma sintering (SPS). Among these materials, UO 2 -diamond composite pellets are of particular interest due to the extremely high thermal conductivity of diamond [4].…”

“…Although the conversion rate is negligible under room temperature, the rate is expected to increase by orders of magnitude under high temperatures [6]. In order to fulfill the density requirement of a nuclear fuel pellet (at least 96.5% of the theoretical density), a temperature of 1400 o C or above is required for the processing of UO 2 -diamond composite pellets using SPS [3]. Under such high sintering temperatures, graphitization of diamond is expected.…”

Multiphysics modeling of UO2-SiC composite fuel performance with enhanced thermal and mechanical properties

“…A large number of materials have been proposed including carbon (in the form of graphite, diamond and nano-tubes) [5] [6], ceramics (such as ThO 2 , SiC, UN and BeO) [7]- [10], and some high temperature metals in various configurations such as homogenous or heterogeneous materials or heat-pipes [11].…”