Open Collections

Spark plasma sintering of cerium dioxide and its composites

University of British Columbia

Cerium dioxide (CeO₂) is an important electroceramic material with a wide array of applications in the fuel cell industry. Recently, cerium dioxide was also found to have similar thermophysical properties as common nuclear fuel materials such as uranium dioxide, thorium dioxide and plutonium dioxide. Thus, it can be used as a surrogate material for simulating the processing of nuclear fuel materials, without the risks associated with radioactivity. However, similar to other ceramic materials, processing of cerium dioxide is challenging, due to its high melting point and low ductility. Consequently, powder metallurgy techniques are widely employed to overcome the limitations of ceramic processing. In this thesis, studies on the processing of cerium dioxide and its composites using a novel sintering technique called Spark Plasma Sintering (SPS) were carried out. The effect of SPS process parameters on the physical and chemical changes of cerium dioxide were investigated. The results indicate that an optimal combination of sintering temperature, pressure and time are required in order to fabricate high integrity CeO₂ coupons. Challenges associated with chemical expansion and stoichiometric instabilities were observed and related to SPS processing conditions, as well as the electric current inherent to the SPS fabrication process.

Text

2017-08-31

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/62930

Mechanical Engineering

University of British Columbia

UBCO

http://creativecommons.org/licenses/by-nc-nd/4.0/