The Effects of Grain Growth on the Intergranular Porosity Distributions in Hot-Pressed and Swelled UO2

Xu, Antai; Solomon, Abraham

doi:10.1007/978-1-4613-1933-7_52

Cited by 3 publications

(2 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Grain growth is detrimental to densification during the sintering process. In one study, UO 2 was produced by hot pressing, however it was found that a large number of pores were present on the grain faces which led to a smaller grain boundary contact area [16]. In this same study it was observed that grains which had not undergone exaggerated grain growth had pores at the grain corners.…”

Section: Present-day Ntp Fuels Researchmentioning

confidence: 88%

CERMETS for Use in Nuclear Thermal Propulsion

Tucker¹

2019

Advances in Composite Materials Development

View full text Add to dashboard Cite

NASA is currently investigating nuclear thermal propulsion as an alternative to chemical propulsion for manned missions to the outer planets. There are a number of materials being considered for use as fuel elements. These materials include tricarbides and CERMETS such as W/UO 2 , Mo/UO 2 , W/UN and Mo/UN. All of these materials require high temperature processing to achieve the required densities. It has been found that Spark Plasma Sintering is a good choice for sintering these materials to the required densities while maintaining a uniform grain size. In this chapter a brief history of NASA's research into nuclear thermal propulsion will be given, followed by specific research by this author and others to produce CERMET fuels.

show abstract

Section: Present-day Ntp Fuels Researchmentioning

confidence: 88%

CERMETS for Use in Nuclear Thermal Propulsion

Tucker¹

2019

Advances in Composite Materials Development

View full text Add to dashboard Cite

show abstract

“…Grain growth is highly detrimental to the process of densification during sintering. It has been demonstrated in partially densified samples of urania produced by hot pressing that a larger number of pores occur on the faces of grains that have undergone grain growth and hence have a reduction in grain boundary contact area, whereas smaller grains which have not undergone grain growth have pores concentrated at the grain corners [5]. The pores located in between the faces of grain boundaries have a greater degree of mobility than those pinned at the corners of grain boundaries [6] and hence in extreme cases the grain boundaries break away from the pores resulting in the encompassing of the pores within the grains [7].…”

Section: Introduction and Overview Of The Spark Plasma Sintering Techmentioning

confidence: 98%